Moderator Post (s) for this thread: >Inside the sinkbydoug seibert on 07/27/2004
sounds like ("Mr. Rooter") is a salesman and not a plumber. your most likely culprit is a clogged vent stack for the bathrooms. the clogged vent is allowning the drain to syphon the water from the trap and allows sewer gas to come back int the rooms thru the sinks.a good check is to remove one on the traps and cheeck how much water is in it. it should be full enough that a small amount will spill as the trap is removed.