I am rehabbing a house in a lake community in the country. The realtor has suggested that I paint the cedar siding. I don't think that painting is appropriate for this rustic house which is 18 years old. Are there any suggestions for treating the siding that will revitalize its look without changing its natural quality?

If your siding is in good shape a good power washing should do the trick, adjust the pressure so the siding does not splinter let it dry a couple of days and then use a good water sealer.
good luck