I guess it really depends on what your climate is like, but I can hoist up a 50'x30' (15x10 m) tarp on poles or simply strung from trees, (my property is covered in oaks). These will last a few years and aren't that costly. I've had temporary shelters built from PVC pipes or 2x2's that have stood for 5 years. You just need the space and friendly neighbors. They can be heated in the cold months and somewhat cooled with a dripping water hose in the warm. If a building is handy, just make a "shed roof" off one side with the tarp. I store a few boats like this now, a couple of 4x4 posts along the free edge and nailed up under the roof overhang. The weight of the outward leaning post, keeps the tarp taut enough.