You will definitely need 2 AC's... Maybe even 3. I'm just south of you. Houston is BRUTAL weather in the summer! But starting small is no harm and will let you feel your way into the project.
Before you get too much further however, you might do some research on RV air conditioners and gennys. A single EU2000 powering a rooftop unit can get tricky due to the surge current requirement. Two AC's get even more tricksy: if one is running and the other tries to start, it will knock the running AC unit offline and fault the genny(s). Even running paralled gennys doesnt necessarily cure this problem.
The solution is to start off with AC's that have a low surge requirement, and can tolerate a surge themselves. Also important is the energy efficiency. Some rooftop units simply will not start and run on a single EU2000.
Suggestion: Check out the newer Atwood AC's: You can run a single 15k btu unit off an EU2000 at sea level. I did it. Atwood even advertises their 13.5k btu unit specifically for this purpose, but the 15k unit is the same compressor and specs.
Link to random vendor for product: Atwood Air Command RV Air Conditioner 15000 BTU Top Unit Heat Pum..
I have no affiliation with this vendor. They were just the first google listing.
I posted this because my situation has similar concerns: 4 chest freezers, a upright refrig/freezer, an exhaust fan, and a 15k btu Atwood AC. Believe it or not, all this stuff is handled by two paralled EU2000's with the eco switches set "on". (We logged three weeks of non-stop running with this setup btw).