I turned a nice sized walk in closet in to my snake room. I have a controlled circulating heater in there that I can program to turn on/off. It turns off when it reaches the set temperature in the room and comes on when it's 2 degrees below the set temperature, so it's always the same constant temp within 2 degrees in the room. Also I used a small tub with water in the corner for humidity. If I need to raise the humidty I just move the tub closer to the heater. I learned this by trial and error so I have spots marked for 50%, 55%, 60% and 70% +/- 1-2%. Not bad for 40.00.

This keeps the temps and humidity in the tubs perfect.