C36 1996 Head leaking
 

I am looking at a 1996 C36 AMG, it has 134,000 miles , upon inspection it looks like it has a slight oil leak on the exhaust side at the front and rear of the head . The leak at the front end goes back around 1.4"this is more than the rear leak which is around 1". The car does not smoke and runs good and the car temperature is good and has not been over heated. It also leaks oil around the oil filter mount.
If I was to replace the head gasket what else would I replace, timing chain, belts hoses etc. I would re machine the heads. Should I do the whole motor or just the top end, if top end what should I replace, springs etc What would I expect to pay for the parts and how may hours would it take, any helpful tips would be appreciated.
Thanks
jdoc