Ball pythons live a long time! 30 years at most. They require proper temperatures, humidity levels, bedding/substrate, food, and enclosures.
Ball pythons tank temperature should be about 80 to 90 degrees Fahrenheit on their hot side, on the cool side keep it in the 70 to 80 degree Fahrenheit range. In Celsius the temperature would equal as: Hot side= 32 degrees Celsius, and cold side= around 29 degrees Celsius.
Humidity is important, too low they snake will be dehydrated, and could develop a respiratory infection (RI), if too high can cause scale rot, and also can cause RI. A proper humidity is 80%, 70% being the minimum. Proper humidity helps your snake shed as well.
For bedding/substrate there are many types you can use, aspen shavings, forest floor, peat moss, sphagnum moss, sand, and wood chips. I prefer forest floor and peat moss. Both hold humidity well, particularly peat. Sand can cause impaction, so avoid it, and a lot of people are against aspen shavings. Sphagnum can become too humid and cause scale rot, but is good to put in your snakes humid hide. Yes sphagnum and peat are the same thing you could say, but they are prepared differently, so they do differ.
Now food, ball pythons can eat mice, rats, and chicks. Mice and rats being the most popular feeder. You can feed live, or frozen and thawed. Frozen and thawed is more safe, as a rat can do major harm to a ball python, and I know some people who have had their snakes die because of this. It also tends to be cheaper. Compare the mouse/rat to the width of your snake, about the same size? Right mouse/rat for them to eat. There are different sizes of feeders, pinkies, pups, weaned, small, medium, large, and even jumbo. Most baby ball pythons start off on mice pinkies, hoppers, or rat pinkies, and sometimes even rat pups. If you don't like this, maybe a ball python isn't right for you.
Suggested enclosure size is 40 gallons, though some people keep their snakes in small plastic tubs. This does not harm them, but I personally prefer the look of a 40 gallon terrarium. It allows the snake to move around, and stretch out.
Can you provide all of this for your snake? Let's look at costs
Now I'm from Canada, so I'll use the prices here.
Light bulbs- Provide uvb, heat, and light- $15-$20+ (Usually depends on wattage or brand)
Hoods- what you put your bulbs in- $20-$50 (Depends on size, and quality)
Under tank heaters- Provide heat- $20-$50 (Depends on size.)
Temperature gauge- to see what your temps are (Some can have both temp and humidity)- $5-$15 (depending on quality, fancy ones are more expensive, cheap ones seem to do just fine though)
Humidity gauge- to see what your humidity is- $5-$15( Same as temp gauges)
Spray bottle/mister- to mist you terrarium to raise humidity levels- $4-$20 (Depending on quality, usually the more expensive ones are better.)
Bedding/Substrate- the flooring of your terrarium, note your animal will be slithering over this, and sleeping on it, so choose wisely- $18-$25 (Depending on the type of bedding/substrate used)
Feeders- What your snake will eat- Mice anywhere from $7 and under-Rats anywhere from $11 under (Know it depends on the size of feeder you choose)
40 gallon terrarium- what your snake lives in-Expensive- anywhere from $800 and under (Depends on quality or brand)
So yeah it's expensive and you need to feed that at LEAST once a month. Also it would seem these light bulb companies purposely make these bulbs cheap and easy to blow, so keep that in mind too. Hoods are fairly durable, but BE SURE not to go over the max wattage, or it'll blow up, literally (From experience). Bedding should be changed when dirty, some people change their's every 6 months, to give you an idea of when to change it. Under tank heaters can be unreliable just like bulbs too, they seem to be made cheaply, and will stop working unexpectedly. Really expensive to keep replacing. Bulbs are very fragile, literally moving the hood the wrong way it will blow. Your snake should be fed every 2-3 weeks.
So for temperature, there's a bit of a preference I've noticed. Some people like 80 degrees Fahrenheit, and some like 90 degrees Fahrenheit. I like a little bit in between personally, about 85 degrees. Same goes for humidity, some prefer 70%, some 80%, and some like 90% even. I personally try to keep it 80%+, and higher during shedding.