J.C.
I have not been to S. Padre in years. However, I have discovered a couple of websites that have made finding travel accomodations so much easier. The first is www.tripadvisor.com. You can find reviews (good & bad) from people who have stayed at various properties around the world. When you go to the website, search "S. Padre lodging." It will bring up choices for S. Padre hotels, specialty lodging (condos), etc. Make your selection & search the reviews. This site is especially good for hotels, but does have some condo reviews, too.
The second site is www.vrbo.com. This site lists condos, homes, etc. for rent by owner. Just click on the state then the specific area to find rentals where you want to go. We have used this site in the past, and just recently booked a gorgeous rental in Rosemary Beach, FL.
You can find all price ranges at both websites. Good luck; hope you have a great vacation!