I recently received a POS inspection with a list of items that needs to be fixed by the seller and seller is giving me the option to fix these items myself with a concession.

All in all we are trucking along but some poor decisions on contractors, missed items on due diligence, and new issues have drained our rehab capital.  

We are weeks from closing the property, though all major items have been agreed upon.

If you accept that for the lease break funds, what incentive does the tenant have for doing anything but moving out the items they want in their new place?

For example: they will likely provide line items for all parts of the house that need work. 

The properties were renovated very poorly, items were missing from the scope of work.

Certainly learning a bit how to spot the for sure items like the '50s 8 inch square floor tile with the associated black mastic, the heating ducts covered in thin white "insulation" as well as attics with the vermiculite insulation gives you a running start by knowing you have to add funds to rehab budget.

If you want to, I would recommend reading this article I wrote that has some more tips on it: https://www.biggerpockets.com/blog/2014-12-23-investing-out-of-state-essential-items-to-vet

My strategy for this deal was to take on responsibility for the POS items, offer no contingencies (after my agent and contractor visited and took video), and all cash.

Hypothetically if it all went into this park and your partnership had a cash call for say a big maintenance item like a septic tank failed, you can't just fund it from your personal checking account.