We are under contract and discussing negotiations with my clients and they are kind of in the position of wanting to ask for the concession but not endanger the deal. Do you think by gauging the receptiveness of a credit at closing would endanger the deal in any way?

You are under contract so they cannot take away the deal you have currently. The worst thing that can happen is you make a request and they say no. Other things that can happen is they say yes or they counter.

Just when you make a request, try to make is as reasonable as possible and show proof of the repair needed and estimates help show “real costs” of the items needing repair.