You aren't going to find a good reptile setup at a big box store, usually just massively overpriced unsuitable ones, trying to keep a ball python in proper conditions in a glass setup is way more difficult anyways. Why not buy a nice PVC setup, set yourself up for success? Or just pick up a simple tub/heatmat combo for the time being if your ambient temp is high enough. Either way have it all setup and running with a quality thermostat (I love herpstats) for a least a week before adding the snake, ensure your temps are correct and stable.