Depends on the age, length and size.

You're 16 foot 150 pound burm will be eating some 15-20 pound pigs, or multiple rabbits, about twice a month.

A 10 foot 50 pound burm will be eating 5-10 pounds rabbits/pigs about twice a month.

Age is a big factor too. Older they get, the slower their metabolism is. If that 16 foot 150 pound burm is 10 years old, you may only have to feed it once a month.

They will hide if you can provide them with one. A lot of times you will not seem them hiding because who has a big hide in their animal plastics cage for a 10'+ burm? Give them a big cage and some hiding spots and they will hide. Now, as much as ball pythons? No. Ball pythons live in burrows dug up by other animals in the wild. They constantly hide.

A buddy of mine gets his rabbits at Livestock Auctions very cheap. Look for a nearby one.