I think the one of the most complete ghost town that we've seen is
Granite MT. The road in was a standard western well maintained gravel road.
Not on your list of states but we visited
Bayhorse Ghost Town just south of Challis ID. It is largely intact but the buildings are barricaded off so you cannot look inside. It is easily accessable maybe 5 miles off Hwy 75.
In Colorado
Animas Forks is a very well preserved town that you can walk around and thru the buildings. It's near Silverton and there was a fair sized crowd looking at the town when we were there. Again there is a good road in from Silverton tho the roads out to Engineer Pass and the Alpine loop would not be a good idea for your camper...heh.
