I used to have to store all my stuff under my covered wooden deck. The roof on the deck kept it pretty dry, and I set all my plastic totes up on a pallet to get them off the ground, then covered everything with a heavy tarp. Was rough, but got the job done. Fortunately I've taken over the larger of two sheds on my property.
The other thing I've done is used disposable materials that I could throw out afterwards, junk I salvaged from someone and used for one year at no cost to myself. Basically see how much you can reduce what you will have left over.
Good luck though.