If you are breeding rats you need at least one snake that can eat jumbo rats. I would personally recommend a red tail boa. There are a bunch of companies out there now that make stackable 48" cages. You could have up to four red tail boas in stacking cages like that and only take up 8 square feet of floor space in your reptile room.

Remember, you are not just feeding off babies that have gotten too big for your collection to eat. You will eventually need to feed off your breeders too. These will generally be rats of pretty enormous size, especially the males.

If you are going to get some boas just as pets and as garbage disposals then you can pick up normals pretty cheap. I have a pretty darn big normal female for sale right now for only $100. I have been using her as a garbage disposal LOL. She ate 6 large rats for me last week LOL.

Long story short...check out Craigslist, Kingsnake, your local paper, Fauna, and other places. You will probably find the right snake pretty quickly.

Another option is to donate your monster rats to a local reptile shelter than could use them. If they are registered with nonprofit status they could give you paperwork that you could use as a tax write off for charitable donation.

There are plenty of ways to take care of things. You just have to find the option that works best for you and yours.