Interesting Challenge
To give you an idea of whats involved regarding setup and parts for the "head" in the Catalina 30, please follow this link:1) go to "resources"2) select Sailing Web Sites3) select Catalina 30 International4) select Technical Library5) select C30 Parts Manual5) Select Section 4 (Systems)6) go to pages 57-58Here is the the plumbing and hardware required to place a permanent head, holding tank, discharge point, etc in the 30. You should already have a sink drain thru hull under or near the v-berth. This will take in the water required for flushing. You should also have a thru hull for the sanitary discharge from the holding tank, which is set up under the dinette port side seat. The big concern is the deck coaming fitting for pump out and the heavy duty sanitary hose that weaves under the galley components. If you have to start from scratch your looking at a bunch of money!! The holding tank can be just as malodorous as a pota potti if not worse. Your waste retention corelates to the holding tank size, so without a ton of chemicals and deodorizers, they can stink up the cabin. The only inconvenience is that you have to empty the pota potti yourself. Better yet if the hose is long enough at the pump out station near you to reach the porta potti tank this might be a better alternative. Then of course if your a real purist, the good old cedar bucket may be the better way to go. I think that the porta potti might be a good choice for now and their are very decent and comfortable models out there.Good luckBob'88 Catalina 30