wow, they charged you 1500 only to give your car back to you in worse condition?
LOL did you get bagged.. wow.

if its something as simple as not starting in the heat, you just need to check the tps, o2 sensor, your connections, and your ignition system.

most importantly, go in that order.
easiest to get to to harder to hardest.

good luck...
if you're trying to find a shop that could fix it for you.. its gonna cost you a pretty penny since it'll require so much troubleshooting, especially with your new tranny problem.