Believe it or not on top of trying to get you and your snake the best settup you can have we are also trying to save you money. All of the things we are talking about do not have to be expensive. If you had not already spent all the money you have it would in fact be a lot cheaper. I have never spent much money on hides. Terracotta pot bottoms to start: $1.10 a piece (I though they were overpriced at that). I forget the price but I picked up heat tape, mite remover, vet approved cleaner and a thermostat from reptile basics for a great price. Then built a rheostat for less than 10 bucks out of an extension cord and a dimmer switch.
Unfortunately for all the money you have spent the real benefit is going to come from a thermostat and a decent one will cost you over $75.
Another point worth mentioning is that lamps are not the most efficient sources of heat. If they were we all have lamps instead of heaters in our house. Not using lamps for heat is going to save you money.