.....What is the best portable toilet (porta potty) to buy for a Vanagon
Westfalia ??? ......
For about ten years now I have used one of the common brand Porta
Potties.  When traveling or camped I normally have the rear bed set up
(or down, depending how you want to look at it).  The PortaPotti fits
perfect under the overhang of the bed, in one corner.  I've never had
problems with leaking or oder.  Two eye bolts and a bungee cord keep it
in place when traveling.  Slide it out when needed, stow it when not.
BTW, when buying, make sure you get the lower model, some are too tall
to fit under the seat.