My dad is handy so I had him build some houses based on graham cracker dimensions. He purchased enough plywood for 4 houses (1 for each grandkid) and began building. They are very sturdy and so are the bases, unlike those plastic ones the kits come with.
I cover them with freezer paper...
Make royal icing and attach graham crackers to the base...
I purchase cheap gum drops, fruit slices, etc and we use those to decorate with. Any leftovers hit the freezer til the next year. We still save a lot of money and they are built to last and be easily taken home without crumbling or the fear of them falling off the base.
Here are a few different years we made them.