Under Contract and AC Needs Repairs/Replacing

[Norman McCullogh]

I am in the process of selling a rental property to the current tenants. My PM just informed me that the AC will have to be repaired or replaced. Repairs will likely be >$1,000, replacement will be about $3,600. I would like to get the tenants/future owners to pay for part of this but don't know the correct way to do so. We negotiated a price based on As-is conditions, including a 14 year old HVAC system, not a new system. There are about five days left of the inspection period, but I cannot let it sit indefinitely with no AC since they are paying rent to live in an air conditioned house. Any advice would be greatly appreciated.