You might want to contact a exterior remodelor who can give you an estimate for a new roof and siding - most real estate agents won't have information about this. The cost will vary greatly depending on the type of roof you put in. I would recommend a standard standing seam metal roof - the type you would find on a pole barn or shed, since it can handle the low pitch in the freeze thaw environment but won't be as expensive as a rubber membrane.
The inspection should be able to be handled by a home inspector (any home inspectors out there that can confirm that?) I can pass along the name of my inspector if you would like to email me through my profile page.