Grace makes the Bernina quilt frame and it is convertible from king size down to baby size - I have it. BUT, taking it apart to change the rollers would be a big job. It's not something you can just snap in and out. You would have to practically re-assemble the frame. If size and space is a problem you would be better off with a frame that can handle 1/2 the size of a king - approx. 60", and when you make a big quilt just do it in two parts and then stitch them together.
Tin Lizzie makes machines in various sizes, so you would have to know the model name or number to know how big it is. But from what I am seeing on their web site, all their machines are either mid or long arm and all would work on a quilt frame.