filed the deeds in the county clerk’s office in Nueces County, Texas.
The record does not show the amounts owing on March 5, 1985, the date of the first foreclosure. The amount owing, however, on the date of the second foreclosure, June 4, 1985, was $60,369.75. On May 9,1985, appellant instituted this suit to request that amounts in excess of lawful charges2 owed to Roberson from the first foreclosure sales be remitted to appellant.
Although the first foreclosure sales complied with all statutory requirements, Roberson and Roberson’s father, acting in the capacity of substitute trustee, purported to rescind the first sales and filed cancellation deeds on May 14, 1985, four days after appellant filed this suit. The reason set forth on each cancellation deed was that “said property had been substantially damaged, prior to the sale, without [appellee’s] knowledge” and that appellee had refused to pay for the property upon discovering that it had been wasted by the mortgagor.
Appellees then posted notice for the second foreclosure sales which were set for June 4, 1985. In response, appellant requested a temporary injunction to enjoin the second foreclosure sales on grounds that the first foreclosure sales were unlawfully cancelled. By docket entry on June 3, 1985, the trial court denied appellant’s application for injunction, and allowed the second foreclosure sales to proceed as scheduled. At the second non-judicial foreclosure sales, appellee submitted successful bids for the deeds totaling $42,500.00 for both lots — $35,000.00 for Lot 4, Block 3 and $7,500.00 for Lot 3, Block 3.
After a non-jury trial, the court upheld the second foreclosures and found that the note principal on both lots, accrued interest, unpaid taxes, insurance expenses, attorney’s fees, and trustee’s fees owed on the property equalled $61,206.11, leaving a deficient amount of $18,706.11. Although Roberson counter-claimed that he was due $69,700.00 in lost rental income in addition to the deficiency, the trial court awarded Roberson $18,706.11 for the “foreclosure deficiency and/or lost rental income.” Roberson was also awarded pre-judgment interest, post-judgment interest, as well as attorney’s fees.
By appellant’s first point of error, he alleges the trial court erred in denying his application for temporary injunction. Appellant maintains that the first foreclosure sales were valid and the cancellation deeds were invalid. Appellant’s second point of error contends the trial court erred in denying appellant’s request for judgment against ap-pellee/mortgagee for the amount bid at the first foreclosure sales, less interest up to the date of the first sale, principal due on the two notes, and reasonable trustee’s and attorney’s fees. Finally, by appellant’s third point of error, he alleges that the trial court erred in granting appellee/mortgagee judgment for damages on the second foreclosure sales.
By cross point, appellee claims the trial court erred in failing to award a judgment against appellant for $69,700.00 in lost rental income.
Addressing appellant’s first point of error regarding the temporary injunction, under the mootness doctrine, appellate courts may only determine cases in which an actual controversy exists. Federal Deposit Ins. Corp. v. Nueces County, 886 S.W.2d 766, 767 (Tex.1994). Thus, when a judgment cannot have a practical effect on an existing controversy, the case is moot. Brownsville Indep. Sch. Dist. Bd. of Trustees v. Brownsville Herald, 831 S.W.2d 537, 539 (Tex.App.—Corpus Christi 1992, no writ). “Courts are created not for purposes of deciding abstract or academic questions of law or to render advisory opinions, but solely for judicial determination of presently existing disputes between parties in which effective judgment can be rendered.” Id. at 538-39.
In Isuani v. Manske-Sheffield Radiology Group, P.A., 802 S.W.2d 235 (Tex.1991), the Texas Supreme Court held that while on appeal of an order granting or denying a temporary injunction a trial court renders final judgment, the case on appeal becomes
2
Lawful charges include the amount of principal on the loans, interest up to the day of sale, unpaid taxes, unpaid insurance premiums, reasonable fees to reimburse the trustee, and reasonable attorney's fees, if any.