If I were using large sweater boxes I would use a plastic shoebox with a hole cut into the lid, cost only $1.00 each. If I were going to use a boot box I would use a 8 cup plastic Glad Ware container with a hole cut out either the top or side, cost of three per container is $3.00 - $4.00. If I were going to use plastic shoeboxes, like you might for your single babies, I would use a 3 cup plastic Glad Ware container with a hole cut on the side, cost of five per container is $2.50 - $3.00. For my adults I use moist peat moss or coconut fiber for all of them at all times of the year. For my babies and really anyone that is intended for market, or too young to be a breeder, I use doubled up moist paper towels.