I recently did a ride with some members of the Land Cruiser Club and our overnight destination was at Hammelhoek, a private game reserve owned by Trevor Roux of Wellinton.
Hammelhoek is situated just north of the bottom of Gannagapas against the Roggeveld Mountains. When Trevor is not entertaining hunters from overseas he has made the place available to local people at a very reasonable "local people" price to cover his running expenses.
So if you are looking for an overnight destination while on a bike trip or a family get away or with friends to the Tankwa, be it all meals included lodging self catering or even camping. Then give Trevor a call and ask him if the place is available and what it will cost you for what you would like to do.
Trevor Le Roux 021 873 2008 tier (at) netactive.co.za