Unfortunately, you have personal connections with the camper, and because of your personal sentiment, you value it more than someone else ever would. In the eye of the seller, it's always valued higher than what the buyer thinks it's worth.
If you really want to sell it, you'll have to just start at a price, and if it does not sell, keep lowering until someone shows interest. And if you get it down to "Free", then really ... it's valuable only to you. Sorry for the harsh reality, I don't mean to hurt your feelings.
On the other hand, depending upon who your market target audience is and who's interested you could potentially get a good price.
Considering it needs work and restoration, just put a price on it an see what happens. Who knows, "American Pickers" may show interest, or some RV renovation television show may find you!
