This is what I would do... If you could get the thing DIRT cheap, a grand at the most, you could always use the roof trusses (very expensive new), scrap the steel (metal like that brings good money) or even re-use it. As lumber prices are very high right now, it would be economical to use as much of the old as possible, but still plan on buying some new materials as well. It also depends on how much time you have... might be better to just write a check for a new one!
If you lived closer to me, I could build a block building for you, but that might hurt your checkbook! :p
