Which environmental controller should I buy?

Hello. I'm new to growing. Started Jan 2020. I decided to build a room in my attic with heating and cooling with a mini split. Room dementions are 14ft long by 6ft wide. This summer has been 100°F all summer. It has stressed out my mini spilt to the point it freezes up sometimes.
My venting... I have 6inch exhaust fan with carbon filter
I have a 4inch duct line supplying fresh air

I just added co2 and I'm really unsure on how to manage all variables. I have a autopilot co2 controller maintaining 1200ppm. Titan regulator to the Titan rain kit.

I was thinking a environmental controller would do me huge. Making my life easier. Which environmental controller should I buy?

I’ve had pretty good luck with the trolmaster products. Easy to add items as you go along too