Figure out the dimensions of the shed you need. In case you don’t have a lot of to store, you do not actually need a large shed, small shed with less materials will satisfy, with less cost. When you currently have a foundation like a patio, a small shed could possibly fit on the foundation reducing the cost for a foundation.
In case you have some cut wood, do not throw it away. The pieces could be used for trimmings and for window sidings and shelves. Drive around your town looking for reclaimed materials around renovations and demolitions areas. They could be used for roofing materials.
With a good shed plans, you will have an exact knowledge of all the materials that you will need. And there you have it. You can save thousands of dollars if you are just patient and diligent enough in searching usable used items.