On ebay you can regularly find used Ranco or Johnson Control thermostats already wired for $50 or less shipped. You can also buy new ones unwired there. Search "thermostats" and bettter yet "Temperature controls". These Ranco's are commonly used by home beer brewers and that's how they end up on ebay. For that price a Zoo Med price may not look so attractive to you. But you can get by with Rheostats or ReptiTemps or whatever until you can do better.