I'd stay away from any live mice being sold as feeders to start a colony and get them from the "fancy mouse" section or from another mouse breeder. I've found some good stock in craigslist, too. I have several colonies of mice- not enough to feed all my snakes but it's also nice to have live mice on hand for babies who won't take f/t pinkies after trying all the tricks.
I keep mine in 10 gallon aquariums with screen lids and small groups of 1 male and 3-4 females. I never take out the male, they are usually good parents and will help the females take care of babies. A new colony wil usually go through a bout of eating their own young before the females figure out what they are doing, so even if this happens I don't interfere (unless it keeps happening and if so it's usually one mouse doing all the killing so I remove the culprit) Taking out mice and introducing new mice stresses out the colony and prevents them from bonding.
I keep my mice on the pelleted horse bedding it is super absorbent and doesn't smell. I give them some aspen and newspaper shavings to nest in and a block to chew, I feed mazuri rodent chow and supplement with occasional seed or peanut treats.
If you invest a little extra in the "fancy" mice you can end up with some really neat looking critters.