Lots of good ideas posted here.
I would urge you to keep you intentions to yourself at this point where you live. There are those who would want to "cherry pick" the good stuff out of you goods for as cheap as they could get them.
If you sell all of the contents as a package, remember 80% of the value is usually derived from 20% of the goods. I'd follow the suggestion to put the most valued items in a room and lock it so that no one could get in. (pull down the blinds and draw the curtains closed too or throw old bed sheets over those items. If asked about the contents of that room just explain you are keeping that stuff to go into your camper van and no that's you final answer if they keep pestering you about it ask them to leave)
There are some sellers who will divide various things into "Lots". Outdoor or Patio furniture etc. Kitchen goods. Refrigerator, Stove, Microwave, Washer/Dryer etc. Shop tools & equipment. Etc. If this is to be auctioned, then it needs to be well advertised for some time and the name of the Auctioneer NOT disclosed. The auctioneer not to have any contact with any of the bidders. In this you may have your best chance at getting YOUR money's worth.
Anything left over could be donated if you have the income posture such that you could write it off your taxes as a charitable donation.