I like to keep an eye on the going market value of cars like the ones I have.  I also see ones like other club members own, so maybe all us Ebay addicts can post them when we see them.  Here's one for a 75 camper like the Schneck's, and here's a 77 Westy similar to ours and the Lewis's.  
It's interesting to see how the way its listed can affect the price, too!  Seems like the 77 could have been titled better!