OPINION BY
Senior Judge FRIEDMAN.Walter Yankowski and his son Steven Yankowski (Appellants), owners of properties at 926-928 Providence Road and 1717 Lafayette Street, respectively, appeal from the March 11, 2009, orders of the Court of Common Pleas of Lackawanna County (trial court), which: (1) denied Appellants’ exceptions to the September 22, 2008, upset sale of their properties; and (2) granted the petition filed by the Lackawanna County Tax Claim Bureau (Bureau) to expose the Providence property to a judicial sale. We affirm.
The relevant facts are not in dispute. Appellants’ properties were listed for a September 22, 2008, upset sale. After neither property was sold, the Bureau sent Walter Yankowski written notice, by certified mail, that the Providence property was scheduled for a judicial sale to be held on February 9, 2009. On November 12, 2008, Appellants filed exceptions to the upset sale. While these exceptions were pending, the Bureau filed a petition to expose the Providence property to judicial sale, requesting the court to issue a rule to show cause directed to all parties in interest. A rule to show cause was issued on December 1, 2008, returnable on December 31, 2008, which provided that a hearing would be held, if necessary, on January 26, 2009. On December 31, 2008, Walter Yan-kowski filed an answer to the Bureau’s petition, and, at Appellants’ request, the hearing on the Bureau’s petition was rescheduled to March 4, 2009.
At the March 4, 2009, hearing, Appellants presented their objections to both the upset sale and the judicial sale; by agreement of the parties, testimony was limited to the issue of notice. Ronald J. Koldjoski, the Bureau’s deputy director, first described the Bureau’s efforts to provide notice of the upset sale.1 The Bureau also submitted posting affidavits, each initialed by a constable, and date-stamped photo*216graphs of the notice posted on each of the properties.2
Written notice of the judicial sale was sent to Walter Yankowski by certified mail on October 8, 2008; the return receipt was signed, illegibly, on October 28, 2008. The judicial sale was advertised in The Scranton Times and the Lackawanna County Jurist on January 9, 2009. Koldjoski testified that the sheriff attempted to personally serve the rule to show cause why the Providence property should not be exposed to judicial sale upon Walter Yankowski but did not find him at his address of record.
Steven Yankowski testified that he received notice of the judicial sale and signed his father’s name on the certified mail return receipt. According to Steven, he did not tell his father of the scheduled judicial sale at that time; however, he retained an attorney and filed objections to the judicial sale on December 31, 2008, again signing his father’s name. Steven testified that he had his father’s permission to sign his name to documents, and Walter Yankowski confirmed that testimony.
Following the hearing, the trial court issued two orders, dated March 11, 2009, one decreeing that both properties were properly exposed to the upset tax sale on September 22, 2008, and the other ordering the Providence property to be exposed to judicial sale on March 16, 2009. Appellants now appeal to this court.3
In tax sale cases, our scope of review is limited to determining whether the trial court abused its discretion, committed an error of law or rendered a decision unsupported by the evidence. Lancaster County Tax Claim Bureau v. Valenti, 144 Pa.Cmwlth. 238, 601 A.2d 445 (1991), appeals denied, 533 Pa. 621, 619 A.2d 702 (1993) and 533 Pa. 647, 622 A.2d 1378 (1993). As the finder of fact, the trial court has exclusive authority to weigh the evidence, make credibility determinations and draw reasonable inferences from the evidence presented. Picknick v. Washington County Tax Claim Bureau, 936 A.2d 1209 (Pa.Cmwlth.2007).
The Bureau has the burden of proving compliance with the statutory notice provisions. /¿.With respect to the upset sale, section 602(e)(3) of the Real Estate Tax Sale Law (Law), Act of July 7, 1947, P.L. 1368, as amended, 72 P.S. § 5860.602(e)(3), states that “[e]ach property scheduled for sale shall be posted at least ten (10) days prior to the sale.” Appellants argue that the Bureau failed to establish that it satisfied this requirement because the constables initialed, rather than signed, the posting affidavits, and the posting affidavits were not notarized. Appellants also complain that the individuals who actually posted the properties were not available for cross-examination. Appellants contend that, under these facts, the upset sale was not valid and, because a valid upset sale is a prerequisite for a judicial sale, section 610 of the Law, 72 P.S. § 5860.610, the Providence property was improperly listed for judicial sale.4 We disagree.
*217An affidavit of posting establishes the presumption that the premises were properly posted. In re Tax Sale of Real Property Situate in Paint Township, 865 A.2d 1009 (Pa.Cmwlth.2005). However, there is no statutory requirement that posting affidavits be notarized in order to be considered competent evidence of compliance with the Law. Id. Indeed, the statute does not require the filing of a posting affidavit. As the trial court observed, in addition to the posting affidavits, the Bureau produced dated photographs showing the upset sale notices posted to the properties. Thus, where notice was the only issue raised with respect to the upset sale, the trial court’s determination that the upset sale was valid is supported by the record.5
Appellants also argue that the Providence property could not be subject to a judicial sale because Walter Yankow-ski was not personally served with the rule to show cause as required by section 611 of the Law, 72 P.S. § 5860.611.6 However, in Valenti, this court affirmed the trial court’s ruling that a judicial sale was conducted in accordance with section 611 of the Law where the property owners testi-fled that they knew of the judicial sale prior to its occurrence. “When a property owner has knowledge of the steps taken prior to the sale, he cannot be found to have been misled to his harm.” Valenti, 601 A.2d at 449. Similarly, the record in this case reflects that Appellants’ actual knowledge of the judicial sale was sufficient to waive the personal service requirements of section 611.
Steven Yankowski received written notice of the judicial sale in October 2008. Admittedly, he had actual knowledge of the judicial sale, which enabled him to hire an attorney, file a timely answer and objections to the judicial sale and arrange to have the hearing continued to March. Steven testified that he handled property matters for his father and that notice to him was as good as notice to Walter Yan-kowski, who also participated at the hearing on the Bureau’s petition. (N.T. at 55.) We conclude that, under these circumstances, where Appellants knew of the scheduled proceeding prior to the sale, filed an answer and were afforded the opportunity to appear and be heard at the hearing, Appellants’ actual notice of the judicial sale waives the necessity for strict *218compliance with section 611 of the Law. Valenti.
Accordingly, we affirm.
ORDER
AND NOW, this 7th day of December, 2009, the orders of the Court of Common Pleas of Lackawanna County, dated March 11, 2009, denying the exceptions filed by Walter Yankowski and Steven Yankowski to the September 22, 2008, upset tax sale of their respective properties and granting the Lackawanna County Tax Claim Bureau’s petition to expose Walter Yankow-ski’s property to a judicial tax sale, are hereby affirmed.
. The Bureau sent Steven Yankowski notice of the upset sale by certified mail on July 25, 2008, and received a signed return receipt. The Bureau also sent notice of the upset sale by certified mail to Walter Yankowski, but the return receipt was signed illegibly, and the box marked "agent” was checked. Thereafter, the Bureau sent an additional notice of the upset sale to Walter Yankowski by regular mail. On August 22, 2008, the Bureau published notices of the upset sale in The Scranton Times and the Lackawanna Jurist. Constables posted notice of the upset sale on the Providence property on August 29, 2008, and posted notice on the Lafayette property on September 4, 2008.
.Koldjoski explained that the Bureau permitted the constables to sign the affidavits using their initials instead of their full names because the constables were concerned about retribution. He added that the Bureau retains a master roster identifying each constable's initials, and he gave the names of the constables who posted the Lafayette and Providence properties.
. By order dated March 13, 2009, we denied Appellants' application for a stay of the trial court's March 11th orders.
. Appellants’ objections to the upset sale are not rendered moot simply because their properties were not sold. Rivera v. Carbon County Tax Claim Bureau, 857 A.2d 208 (Pa.Cmwlth. 2004), appeal denied, 583 Pa. 692, 878 A.2d *217866 (2005). At an upset sale, where there are no bids of the upset sale price, all rights in the property, i.e., legal title, are transferred from the owners of the property to the tax claim bureau as trustee by operation of law. Id. However, the divestiture of ownership that follows exposure of property to an upset sale cannot occur when the notice requirements of the Law have not been satisfied. Id.
. To the extent that Appellants presented other arguments to the trial court, we note that proof of posting is the only issue raised on appeal with respect to the validity of the upset sale.
. In pertinent part, section 611 of the Law states as follows:
Service of the rule shall be made in the same manner as writs of scire facias are served in this Commonwealth.... If service of the rule cannot be made in this Commonwealth, then the rule shall be served on the person named in the rule by the sheriff, by sending him, by registered mail, return receipt requested, postage prepaid, at least fifteen (15) days before the return day of the rule, a true and attested copy thereof, addressed to such person’s last known post office address. The sheriff shall attach to his return, the return receipts, and if the person named in the rule has refused to accept the registered mail or cannot be found at his last known address, shall attach evidence thereof. This shall constitute sufficient service under this act.
72 P.S. § 5860.611. Neither party refers to Bureau Exhibit 17, which is a sheriffs "return not found” and appears to satisfy the requirements of section 611. (R.R. at 99b.)