*nod* This seems reasonable. I haven't done insulation before, but the vac has, and I've watched it done before. The big trick is basically to get the stuff with backing, wear protective clothing, and get a nice staple gun. It's quite simple, just tedious. But really, with insulating, you'll mostly be paying for materials with a contractor, there's not a lot of labor involved, so it might be easier (and faster) to do it with a contractor, especially with the awkward spaces you're looking at doing. Weatherstripping is pretty darn simple, I've done some, the vac has, and Mom has as well. *shrug* Depends on how much you'd prefer do-it-yourself over contracting out, really.

The vac says: or, at least for insulation and weatherstripping, you could pay us gas money and we could do it.
(I agree. It won't look uber gorgeous or anything, but insulation doesn't, and we'd do it without damaging anything or doing it very poorly. We have insulation on much easier spaces to do at this house and I could easily put up a roll or so for practice before we headed out to do yours, if you like. (Managed to find a ridiculous deal on a miss-order for insulation so we have a ton to put up that likely still won't cover all of our attic roof line.))

*hug*
Good luck!