a head gasket is not more that $100, a HEAD might be $1100.. and you would need a gasket to put it on.

this is a tough situation. 1. you need a better dealer (or service). 2. your putting factory new, factory priced parts on a 75K miles car. 3. It doesnt seem (not to offend) that you know what is being done for the price you are paying. uninformed, you always get screwed.

get an exact explanation. ask about a rebuild/used head or engine. You should be able to get this fixed much cheaper.