Ed, in the end, all of these repairs you listed will cost far more than you'd expect. Most will require building permits (more 'Kaching-Kaching').
My question is, on the other issues, what is the normal process to have these fixed.
1. Do I get quotes and then renegotiate the sale price. Given the extent of what's needed hire a General Contractor to give you a 'one bid' price. Might this cost a bit more? In a word yes, but he's the one whose going to assure the work is done properly. Secure the building permits, construction inspections, etc.
2. Should I expect the seller to fix these issues. Unless you got one hell of a deal going in the answer is normally 'yes.' ("Good money after bad" as we say 'over here.) What you need is an appraisal (you'll need the contractor bids) done in "As will condition." Or what will the place be worth after the work is done. Will it be worth more than your "total cost of acquisition?"
3. Should I share the inspectors report with the owner. No reason not to, and the Realtor's involved. Reason is you're back at the negotiation table.
In a nut shell this place hasn't seen a bit of preventive maintenance for years. Even fixed, you'll will be finding out this is just the start, not the end ....
Edit: For context above I was in the residential lending business for 35 years.