Before taking any decisions, any aspiring snake keeper should stop and give great consideration to the responsibilies involved. Realise that its being confined to a cage means that the snake cannot take care of itself, and YOU are responsible for its welfare and all its requirements. This subject is tied up with several other factors, size, housing, feeding, cost and family considerations. Each has its own chapter, and this section should be considered an overview. There are people whose worst nightmare is a snake, their feelings should be respected and positive response received before embarking on your purchase.
Housing is another major consideration, tied in with size.
You will need to find out what the maximum size your snake is likely to grow to and plan accordingly. Reckon on 1 square foot of floor space for every foot of snake as a minimum. The housing can be increased in size as the snake grows, but this obviously adds to the expense. Costs are another area that are not always immediately obvious. The vast majority of snakes will have to be kept in an artificially heated and lit environment, the heating will need to be on 365 days a year normally, and the lighting up to half the time.