After many years motorhoming, I think it is time to hang up my spurs. The problem now is figuring out what an unusuaL motorhome is worth. It is a 2007 RHD Wingamm OASI 540 on a Fiat Ducato base with 35000 miles on the clock. It is a monocoque construction - never a single leak. It's in very good condition and fully equipped. Its USP is a wonderfully comfortable large drop down bed, although you can also make up a double below. I haven't ever seen seen a second-hand one for sale so..... how do I value it for sale? Any hints gratefully received.