How much is a pastel ball python?

Hi i live in Chicago Illinois and i am planing to buy a snake.. but i don't know were to buy it.. how much it will be in a show like Scott Smiths’s all Animal Expo ???? do u guys know?? i have some other questions.. do they smell bad? what is better female or male..? and my 20 long tank will be OK for it..? what Cain of bulb should i buy?? uav or Infrared??? what is better and easy to clean sand or what other stuff is better??? and what are the temperatures that they need.... please help me i am new with this!! Thank u!!!