If you happen to live close enough to Mountain City, GA to go pick it up, my very lightly used strap on popup camper bike rack is in an online auction there. Not going to admit how much I paid for it but, pretty sure you can get it for a LOT less than I paid! Worked great we just out grew the popup and sold it a few years ago. The bike rails are adjustable and offset now to work with campers with an AC unit on top.
Sixnal Bicycle Rack for Pop-Up Camper Top
Sixnal brand aluminum collapsible frame made to hold up to four bicycles. Currently configured for 3 bikes with additional attachments for a fourth. Each corner has an orange plastic adjustable height foot to protect the camper top and there is a ratchet tie down at each corner. Comes with...