Okay, I really don't want to sound mean... If you cannot afford proper husbandry for an animal, you really should not get one. What happens when your ball python gets sick and it needs a vet? Seems a little unfair. I understand what it means to have no money. I lived for 4 years on welfare. After that I worked for minimum wage at a coffee shop. I know what it means to have little money. You cannot have an animal in a situation where you cannot afford to get it what it needs. It seems unfair, I know but the ball python did not ask to be put in a situation where it cannot live in home that it needs. You need to find a heat pad... Kijiji or craigs list is a good place to start for a second hand one. Dimmer switches can be found for $10 at any hardware store. If you have it... soak a few pieces of paper towels and place them staggered around the cage. Works well but moss would do better. Cover the top of the cage with Aluminum foil leaving a small hole for the heat lamp. This will help prevent the moisture from escaping.

The best place to get information is on sites like this one and google is a really good place to start. Pet store employees are horrible for information. We can help you where we can on this site and will give you the information you need. It is up to you to choose what you think is right.