FHA Seller's Concession Limits?

Hey everyone. We put an offer in on a 2-flat in Chicago and we requested a 3% closing cost credit, which was accepted. They've now came back in reply to our inspection requests stating that they'd like to provide a $2,000 credit at closing rather than complete repairs. My question is this: What is the maximum seller's credit? My understanding is that if they go over the maximum, my lender won't accept it and will take it as a lower sale, but depending on the site I look at, some say 3% max and some say 6% max.

If it is a 3% max, I'm guessing the only thing I could ask is that they complete the repairs then? Thanks in advance.