Ha guy above me got you covered and typed on his phone faster than i could. But check out Amazon and Craigslist for equipment as your best bet, also as previously mentioned make sure your light comes with a dimmer ability.
Yes it does get much more expensive aside from the price of the snake, the equipment, and continuing care of an animal that can live for 30 years! haha i believe it is more than worth it but you need to be sure you are dedicated to the health and prosperity of also.
There are much cheaper alternatives to housing that id love to suggest, if you could share a little more info so i could get really specific for you.
For starters you can pick up 20-50 gallon tanks in better or worse condition on your local classifieds or craigslist. You can also find used heating or other reptile equipment that way but for new the best option is probably Amazon. you can order basic to pretty advanced equipment at close to if not the lowest possible price. including, thermometers, heat pads, lights, etc. If im not mistaken there is also heat tape and such which seems to be the preferred method of heating by breeders.
A single lamp or heatpad paired with a thermostat, depending on your locality and the general conditions of the room your snake will be living in will be more than enough to provide the conditions necessary providing you check with the proper measuring instruments to maintain that.
ceramic heating is also a viable option
https://www.amazon.com/Zilla-Reptile...snake+heat+pad
https://www.amazon.com/Thermostat-Re...ake+thermostat
https://www.amazon.com/Zacro-Reptile...+heating&psc=1
What area are you located and how are you planning to purchase the snake? online or locally at a pet store?
A youngling or a subadult snake?
And you are familiar with the temperature and humidity requirements for balls?
Ball pythons can be great starter snakes, most are very friendly and do enjoy being handled to different extents, of course as always most problems pertain to husbandry, I've never seen any trouble with my snakes personally (all ball pythons) a buddy of mine did have a snake that was very tentative to eat and another friend had a snake that regurged a regular size mouse once 24 hours after eating, but continued to eat normally at the next offering just longer than a week later.