The best thermostat is a herpstat (you can get a herpstat 1 basic), or you can get a vivarium electronics.
I've gotten the cheap $30 thermostats like Jumpstart before, and they do work, but they become very inaccurate in under a year... and then you still have to get a new one. I realized it's best to just start with the best LOL, it saves more money in just a few years.
I'd also rec getting a temp gun! It's needed as a double-check for your temps, in case your other equipment is faulty, you would know.