Folks you do not have to be held hostage, you can still buy dumb thermostats for instance.

And here's a life tip. The thermostat sends a low voltage signal to the air conditioner compressor controls outside, that low voltage signal closes a set of contacts which conduct Power to the compressor. So simply bypass or manually close those contacts and you can run.

I don't wanna explain too much more, people who don't understand based on 'just' that should ask someone with electrical experience for help, it can be dangerous if you mess it up.