How much would it cost to fix a head gas gasket for a 95 Audi A6? Please Help!!!?

I want to know cuz I am selling my car. I need an exact or very close to price.

How much would it cost to fix a head gas gasket for a 95 Audi A6? Please Help!!!?you cant fix a head gasket you have to replace it call up the Audi dealer and ask him the question