So for those of us in small houses and maybe not even a garage, I think I have a pretty good solution for how to keep a layout intact year round- I built a workbench lid over it. I have a one car garage which is jammed with stuff. All of my shelves have plywood bases with casters so I can easily roll shelves around and get to stuff buried in the back. I built shelves under my layout and put the whole thing on wheels but I still had to issue of not having anywhere to work on other projects without having to put the layout away first. Solution- use 2x3s to build a basic frame and cover it with a sheet of luan for light weight. Three barn hinges attached the lid with strength to rotate open and closed without fear of breaking loose. There is about 9.5" of vertical clearance, so plenty of room for buildings and scenery which are still in the planning stages. Hopefully, you can adapt my project to find a way to keep your layout up and running year round in tight quarters. Pics are at my website, see signature below. Thanks!
Original Post
Necessity is the mother of invention. 
