Due to internal coolant leak, do my car nead new head gaskets or intake manifold

What is your question?

My car started smoking from under the hood and started over heat a little. It didn't get all the way to the red part because I turned it off. Before I turned it off, I heard bubbles sounding like they came from under the hood somewhere. I checked my coolant and nothing was in there. I haven't drove the car since. My mechanic said that my head gasket is cracked and I will have to pay $1000 to get it fixed. I didn't have any smoke coming out of the tail pipe and it only overheated once. Is this my intake manifold or head gasket? I don't want him to try and cheat me