If the plywood on your roof is soaking wet, it will take a long time to dry out. If it has been soaked for a long time, there may be water underneath, in the insulation. I would be prepared to replace the plywood and the insulation, in fact, I'd definitely plan on it. The cost of new plywood and insulation won't be that much but the labor will be a lot more.
I think the heated storage for cheap and the cheap labor would get me indoors. It may be that once you get into the roof it will take some time to get it done.