This isn't an answer MM, but I would ALWAYS buy such a thing as this off a trader and not privately. We bought an American motorhome from a trader, then 6 months later got a letter from a finance company demanding to know where it was as there was an outstanding balance on it and they intended to repossess.
We sought legal advice,and if we had bought it privately,we would have had to let them take it,we found the advert out of the MMM as proof we had purchased from a trader,so they could do nothing. Phew !!
Sorry it doesn't answer your question,but if it helps,we are involved in the motorhome ' scene ' quite heavily, and have heard no negative comments on Emm-Bee. Good luck x