I asked the Seller for concessions to repair items that by my estimate will cost $2-4k, and also let us know where the crawl space access is.

So that may be an item to discuss as well.

What are some common items that a buyer/agent should try to negotiate on?

If you are comfortable you have built in enough reserves for vacancies, maintenance, capital expenses (sounds like most of the major items are new) then it does not sound crazy to me. 

I feel like one item that I'm missing is the budget.

What about the % being put away for things like repairs or future capX items like hvac or roof (although it's new now, something could happen that would warrant replacement). 

[drywall]), insulation (more bat in the cavity but not too much where you mess up the 3rd factor , decoupling: resilient channels and double stud walls are for this, The 4th item is sealing openings and penetrationsThere a lot of different levels and it comes down to is this going to be a separate unit or just a finished basement.

Someone will need to take the time to help him draft a letter of explanation for items on his credit report.

If you figure $20K for land you'll depreciate $60K over the next 27.5 years which puts you at $2,100 a year you can write off as a "loss" (assuming you itemize which should be a given for any RE investor)  I agree that this looks like a minimal cash flow property with some risk, but if you want to build equity and know it will rent you will at least keep your head above water on it.  

The investor just lost his $25,000.The redemption price tag also includes taxes and insurance paid or owed by the current owner.If the borrower makes written demand for redemption, the current owner has 10 calendar days within which to reply in writing with an itemized redemption amount.