Mercedes Benz repair: head gasket, head gasket replacement, honest mechanic

Question
I have a 1999 CLK 320 which may need a head gasket replacement.  Can you
give me an idea of how much it is to replace a head gasket in this model.  Also I
was reading about a product called Steel Seal to be used instead of replacing the
head gasket - does this work? what is your opinion on this?

Answer
Firts off I would confirm myself by doing a compression check on the cylinders as far as needing a head gasket I would also look at the exhaust and see how much white smoke is blowing out of the exhaust (white smoke) I would not advise using additives, A good mech would do it for 800 dollars plus parts, but since people think its a MB they tend to go overboard, Ive personally done HG for less than 600 dollars,partys are about 130 dollars for the set that includes intake exhaust and all other gaskets, I would just honestly find a good honest mechanic that can work on MB or BMW