Some people are problem solvers and actually derive enjoyment and other personal benefits from troubleshooting problems, coming up with solutions and executing on them. 

Quote from @Ana Vhan: Go to YouTube and search "air conditioner troubleshooting" and you will find ton of videos that show you how to diagnose yourself, as well as preventative maintenance tips.

I'd troubleshoot/replace the heating elements and/or t-stats.

Does anyone know what else I could troubleshoot before having to pay someone?

I got into the computer software world when you could just be a good troubleshooter and problem solver.

This is a general troubleshooting guide for when you get the error code 9000 in QuickBooks.

I saw a work order from the management company late last night saying the ac stopped and today, Sunday, went over in the morning to try and troubleshoot it.

It basically works like a hotel.If I were to rent it myself I'd likely make a touch more but me spending any time trouble shooting etc is not worth it right now for me for this property (I live 2 hours away and work full time).

Maintenance calls are troubleshooted over the phone if possible, then someone from their team goes out to try and fix it, (at no cost to us) if that still doesn’t work they’ll get a licensed contractor out which of course then would cost us their prices. 200+ units.

@Ross Bernard So did you pay him or offer to pay for his time to trouble shoot the problem?