Lead in water...solutions?

[Angela Vestal]

We have a house under contract that has a well and so we had the water tested.  There is lead in the water from the kitchen sink that is 7 times the reportable level.  The water testing company says that usually lead is not in wells, that usually it comes from the solder used on copper pipes. The house was built in 1992 and there are copper pipes. He suggested either replacing all of the plumbing in the house or getting a whole house reverse osmosis filtration system.  Has anyone else had this issue?  What did you do? I've never replaced all the plumbing in an existing house.  What is the cost comparison between replacing and filtering?  Can someone explain how the reverse osmosis system works?  Is there a filter on each faucet?  It seems to me that if the water is filtered and then put through the same pipes it will become "re-leaded?"