my piggies started off in a ramped cage (2 storey) dont expect much movement off them for a while, they will investigate ect. after they get started most the time their's no stopping them. whenever i open the cage doors they zoom downstairs *which has 2 be the hardest one to open* i think if you look for a guinea pig hutch 2 storey and are worried you should always ask the seller about them. i got tips of putting the food downstairs but most of the time i train them, by putting them on the stairs to walk down, and just put a small place to snuggle into their, food, bottle incase they cant get up. it will eventually go up, if its partner cant go downstairs, or does and annoys him and normally they copy each other!