(dissenting in part and concurring in part) —I agree with the majority that defendant, Greg Thomsen, should prevail. However, the divergent legal theories leading to that end necessarily produce results that differ in kind.
While acknowledging that a vast preponderance of the *418courts and legal authorities agree that a conditional sale is not a “loan or forbearance”, the majority goes on to say that there is now respectable authority to the contrary. It is of note, however, that few of the authorities go to the extremes of the majority opinion to avoid the fact of “assignment” and to adopt a theory of “agency” that is so necessary to its outcome.
The majority ignores the fact that the plaintiff bank was injected into the case as an assignee of Carter Motors, the automobile’s original vendor. The opinion is based primarily on an assumption that a relationship of lender and borrower existed between the bank and Greg Thomsen. But, in doing so, the majority ignores the trial court’s finding of fact that no contact or negotiations took place between the bank and Thomsen. The legal chasm is bridged by the simple expedient of declaring that Carter Motors was an agent of the bank.
This unique factual position is derived by ignoring the trial court’s findings of fact without first having determined that they were either opposed to or unsupported by substantial evidence. In effect, the majority made its own findings on the subject of agency despite findings or lack of findings made by the trial court. Further it stems in part from the majority having accepted certain of Thomsen’s unchallenged testimony. This, of course, flies in the face of numerous cases in which we have held that a trial court need not accept or give credence to testimony merely because it is unopposed.
Finally, the opinion may solve one litigant’s immediate problem, but it does so by adopting a view that is decidedly minority in nature. It also makes a 180 degree turn which may place in jeopardy thousands of longtime commercial transactions made in good faith and in reliance upon our prior adherence to the view held by most courts and other legal authorities. This not only may have an adverse effect upon assignee banking institutions but on many small individual assignee holders of such paper.
The change should not be entered into in such a cavalier *419fashion. In fact, it is an unnecessary step. At the time in question Thomsen had statutory relief available to cover the problem he faced. Unfortunately, the statute was mentioned by the majority but its effect was passed over.
At the risk of prolonging this, I am compelled to review the facts and statutes in existence at the time the case arose.
Greg Thomsen, the defendant, decided to buy a new automobile. On Saturday, July 31, 1965, when he entered Carter Motors, Inc., he was the owner of an old Studebaker and had $1,000 in his pocket. The car he wanted was in stock. As a result he emerged a few hours later with a new Volkswagen, a potential lawsuit, and copies of two written documents (i.e., one was entitled “Purchase Order” and the other was entitled “Automobile Conditional Sales Contract”) . Each document had been executed by him, within a short time of the other, during separate conferences with the Carter Motors’ salesman.
Monday, August 2, was the next business day of the Ballard Branch of the National Bank of Commerce. On that date, Carter Motors assigned to it the “conditional sales contract”.
Greg Thomsen paid all installments to the bank up to and including the one due July 15, 1966. Thereafter he made no further payments.
The bank, as assignee of the “conditional sales contract”, sued for the balance said to be due thereunder. Thomsen answered and alleged that the true transaction did not involve a “conditional sales contract” but in fact was a “loan” for the balance due on the purchase price of the automobile. He also charged that the alleged “conditional sales contract”, and its subsequent assignment to the bank, was a sham to cover the true “loan” transaction between himself and the bank. By way of a partial defense, Thom-sen asserted that the “loan” was tainted with usury.
The trial court held that the transaction involved a “conditional sales contract”; that the “service charge”, in the form of a “time price differential” (amounting to 14.61 per *420cent per year), was not unconscionable; and that the law of usury does not apply to “conditional sales contracts.” The court entered judgment for the bank in the amount of $844.75 (which included “service charges” in the form of “time price differential”), and awarded $100 attorney’s fees as well as costs and disbursements.
Thomsen has appealed, assigning error to 11 of the trial court’s findings of fact. Essentially, it is urged that the trial court should have believed testimony supporting his theory of the case. In this regard, it is clear the trial court found it necessary to resolve several disputes of fact and decided them in favor of the bank. It is not our function to reevaluate the credibility of witnesses. In re Estate of Kleinlein, 59 Wn.2d 111, 366 P.2d 186 (1961); Sheldon v. Hallis, 72 Wn.2d 993, 435 P.2d 988 (1967).
Thomsen asserts that although the Carter Motors’ agent (i.e., the automobile salesman who had prepared both the “purchase order” and the “conditional sales contract” for Thomsen’s signature) was available, the bank failed to call him. Thus, Thomsen argues, the trial court erred by failing to find that had the salesman been called he would have testified adversely to the bank and would have supported Thomsen’s theory that a “loan” had been transacted.
The argument is not well taken. The failure to call such a witness creates no more than a permissive inference. Wiehl, Instructing a Jury in Washington, 36 Wash. L. Rev. 378, 386-90 (1961); National Conference of Commissioners on Uniform State Laws, Uniform Rules of Evidence, Rule 13 (1953); 1 B. Jones, The Law of Evidence § 9 (5th ed. 1958). It neither takes the place of evidence of material facts nor shifts nor satisfies the burden of proof so as to relieve the party who has that burden. 31A C.J.S. Evidence § 156 “Strength of Inference” at 417 (1964).
A review of the full record reveals that, with the exception of findings of fact 3, 9, 12 and 13 (to be discussed hereafter) all are supported by substantial evidence. Thus, .they should be accepted as established facts. Leonard v. Washington Employers, Inc., 77 Wn.2d 271, 461 P.2d 538 *421(1969); Moss v. Vadman, 77 Wn.2d 396, 463 P.2d 159 (1969). This being the case, one must conclude that the instrument upon which the instant action is based was a “conditional sales contract” and not a “loan”.
Mr. Thomsen contends we should overrule Hafer v. Spaeth, 22 Wn.2d 378, 156 P.2d 408 (1945). Hafer holds that a bona fide “conditional sales contract” does not constitute a “loan” of money; that “handling charges” are not “interest”; and that such a transaction does not come within the purview of the usury law.
It is argued that in an age when the financing agent has become so intimately involved in the original sales, the reasons relied on in Hafer no longer ring true. Nevertheless, the basic rule in Hafer still remains the prevailing view. 6A A. Corbin, Contracts § 1500 (1962); 6 S. Williston, A Treatise on the Law of Contracts § 1685, at 4766 (rev. ed. 1938); 2 Restatement of Contracts § 526, illustration 4 at 1023 (1932); Annot., 104 A.L.R. 245 et seq. (1936); 14 A.L.R.3d 1069 etseq. (1967).
Subsequent to Hafer the legislature adopted the Retail Installment Sales Act, RCW 63.14.010 et seq. In so doing, it not only authorized the use of “service charges” (which includes “time price differential”), but when the instant contract was executed in 1965 the legislature still had not limited the amount of “service charge” that could be imposed.4 Thus, it cannot be said, as a matter of law, the trial court abused its discretion by holding that a “service charge” amounting to 14.61 per cent per annum was not unconscionable.
Despite the legislative amendment of 1967 and the 1968 amendment by initiative limiting the amount authorized as a “service charge”, “service charges” were neither eliminated nor restricted in their application as proper costs of *422obtaining a conditional sales contract nor were they characterized as “interest” paid on a “loan”. Thus, one must conclude that “service charges” authorized by the Retail Installment Sales Act are not subject to RCW 19.52.030 covering usury.
The legislative history of the Retail Installment Sales Act has served to emphasize, not abrogate, the difference between “loan” and “sales”, “interest” and “service charges” with which Hafer was concerned. In light of circumstances existing at the time the instant contract was executed, we should not overrule Hafer v. Spaeth, supra.
The trial court’s memorandum opinion was incorporated in its findings of fact and conclusions of law. That opinion makes it evident the outcome of the case was governed by the 1963 version of the Retail Installment Sales Act. RCW 63.14.010 et seq.
The act authorizes the imposition of a “service charge”. Nevertheless, it also provides that a seller may not recover it if he fails to obey the requirements of the act. RCW 63.14.180; In short, full compliance with the act was an issue necessarily involved in the instant litigation. In this regard, it is clear the trial court felt there had been full conformance. The bank’s brief makes it equally clear that, in its opinion, its assignor had fully complied. Thus, the necessity of acting in accordance with the statute is properly before us. Maynard Inv. Co. v. McCann, 77 Wn.2d 616, 465 P.2d 657 (1970). It is not being considered for the first time on appeal.
The trial court found that Thomsen signed the “conditional sales contract” (exhibit 1) on July 31, 1965. It appeared to have been prepared in compliance with the Retail Installment Sales Act. It contained the requisite terms for payment of “time price differential”, a breakdown of the monthly installments to be paid, and the other items required by RCW 63.14.040. The instrument was signed the same day by Wade Carter, an officer of Carter Motors. On August 2, 1965, Carter Motors assigned it to the bank. The *423“conditional sales contract” pertained to a deluxe 1965 Volkswagen sedan, model 113, serial No. 115 859 858.
The statement of facts and exhibits indicate that only a few hours prior to executing the “conditional sales contract”, a Carter Motors’ salesman filled out, and had Mr. Thomsen sign, a “purchase order” (exhibit 4) for exactly the same vehicle (i.e., a deluxe 1965 Volkswagen sedan, model 113, serial No. 115 859 858). The vehicle was actually in stock and was to be delivered to Mr. Thomsen in a matter of hours. The purchase order was signed by both Mr. Thomsen and the salesman.
Mr. Carter explained that ordinarily a “purchase order” is not binding without his personal signature. He testified, however, that he accepted and acted on it despite the lack of signature. In explaining the “purchase order’s” significance, he said:
This is the offer and acceptance. It states what type of car that he is buying for how much and how.
The “purchase order” (exhibit 4) signed by Thomsen contained all data required to place it within the purview of the Retail Installment Sales Act with the exception of: (1) “the dollar amount or rate of the service charge” and (2) “the amount of time balance owed by the buyer to the seller . . .” RCW 63.14.040. It even provided, as did the “conditional sales contract” (exhibit 1), that the purchaser would not receive title to the automobile until final cash payment was made. It also provided, in a manner similar to the “conditional sales contract”, for the balance to be paid in 36 payments of $33.79. Thus, it was much more than a mere “purchase order.” It was a contract that provided for installment payments as well as “service charges” (computable from the payment schedule) and contained a security agreement. With the two exceptions listed above, the “conditional sales contract” and the “purchase order” covered the same property, contained identical terms of payment and had similar terms of security.
Herein lies the problem. The “conditional sales contract” *424(exhibit 1) specifically provides for a “time price differential” of $242.15; the “total time balance” of $1,216.44 is listed as required by RCW 63.14.040. On the other hand, the “purchase order” (exhibit 4) has a line drawn through the space for “contract balance”, it provides for a “balance to be financed” in the amount of $974.29, and yet simple computation indicates the installment payments include an undisclosed “service charge” or “time price differential” that would produce an undisclosed “total time balance” of $1,216.44. Such failure to disclose these items does not comply with RCW 63.14.040.
Each document was completed within a short time of the other. They are in similar, although not identical, terms. Each is enforceable and could lead to a similar legal result, yet, each has a real potential for a conflicting interpretation. At best, it can be said that Carter Motors’ preparation of the two documents for Thomsen’s signature created both an ambiguity and a lawsuit.
The trial court erred in finding of fact 3 by failing to reflect that the transaction was contained in two documents (plaintiff’s exhibit 1 and defendant’s exhibit 4) rather than in one.
Finding of fact 12 was in error wherein it held that the “conditional sales contract” truly and fairly set forth the transaction between the parties. It, like finding of fact 3, failed to reflect that the true transaction was contained in two documents.
RCW 63.14.020 provides in part as follows:
Every retail installment contract shall be contained in a single document which shall contain the entire agreement of the parties including any promissory notes or other evidences of indebtedness between the parties relating to the transaction . . .
(Italics ours.)
Obviously, the foregoing provision is designed to protect a buyer from deception or from ambiguities that may arise from the existence of more than one document covering the same transaction.
*425Whether the two contracts may have merged or may have become integrated is not before this court. These common-law doctrines were not changed by RCW 63.14.020. A seller’s failure to comply with the “single document” provision does not render the contract unenforceable, it merely restricts the seller’s recovery to “an amount equal to the cash price of the goods and the cost to the seller of any insurance included in the transaction.” RCW 63.14.180.
If a seller desires to impose the authorized “service charges”, he must comply with the act. If he fails to do so, he
shall be barred from the recovery of any service charge, official fees, or any delinquency or collection charge under or in connection with the related retail installment contract or purchases under a retail charge agreement . . .
(Italics ours.) RCW 63.14.180.
Carter Motors prepared, and had executed, two similar documents covering the same motor vehicle. Each document was legally enforceable on its face. One was assigned to the bank (exhibit 1), and the other was retained in the files of Carter Motors (exhibit 4). This violated the “single document” provision of the Retail Installment Sales Act. RCW 63.14.020. As a result, Carter Motors would not have been entitled to recover “service charges” and “collection charges”. RCW 63.14.020, 63.14.180. The assignee bank stands in the shoes of its assignor. 3 S. Williston, A Treatise on the Law of Contracts § 432 “Rights of the Assignee Against the Debtor” (3d ed. 1960).
Finding of fact 9 was in error wherein it stated that $844.75 was presently due and owing the bank under the “conditional sales contract.” That amount incorrectly included “service charges” to which the assignee bank was not entitled. RCW 63.14.180.
Finding of fact 13 pertaining to the award of an attorney’s fee is also in error. Under RCW 63.14.180 the assignee bank is not entitled to collection charges. Costs of collection or collection charges include an attorney’s fee in connection *426therewith. McClain v. Continental Supply Co., 66 Okla. 225, 168 P. 815 (1917); Letcher v. Wrightsman, 60 Okla. 14, 158 P. 1152 (1916); Cox v. Hagan, 125 Va. 656, 100 S.E. 666 (1919); see also Ben Constr. Corp. v. Snushall, 44 Misc. 2d 878, 254 N.Y.S.2d 948 (1964) in which the phrase “delinquency and collection charges” was held to include attorney’s fees.
The plaintiff bank, as assignee of Carter Motors, is entitled to judgment against defendant Thomsen. However, it is not entitled to collect any “service charges” in the form of “time price differential” and it is not entitled to an attorney’s fee.
The application of this case to the “single document” provision of ItCW 63.14.020 should be prospective insofar as it is concerned with the combined use of “purchase orders” of the type here involved, and “automobile conditional sales contracts”.
One final point must be made. The majority states that the purchase of a conditional sales contract is a loan of money. For support of that proposition they cite State ex rel. O’Connell v. PUD 1, 79 Wn.2d 237, 484 P.2d 393 (1971). That case does not support the proposition.
O’Connell holds merely that the purchase of a vendor’s interest in a conditional sales contract is a loan of money to the vendor, from the one who purchased the vendor’s interest in the contract. Even under the facts used herein by the majority, no such proposition is before us. The majority should not attempt to extend O’Connell beyond the facts and the law stated therein.
The judgment should be modified and affirmed as suggested herein.
Donworth and Weaver, JJ. Pro Tern., concur with Stafford, J.
Petition for rehearing denied June 12, 1972.
Subsequent to the instant transaction, RCW 63.14.040 was amended in 1967 to limit “service charges” to 18 per cent per annum computed monthly. In 1968 it was amended again, by Initiative 245, to provide that “service charges” were limited to 12 per cent per annum computed monthly. In this regard see RCW 63.14.040(2) (d).