Tandem trailer towing

I've seen some trailer setups using custom built trailer where a rack was built from the boat trailer frame rails above the boat to haul other toys. Mostly I see boats with two jet skis above, but I've also seen boat with a sandrail above and a boat with two quad runners above. I've even seen a boat with another boat above. So you could have a boat with a popup above.

Personally I would change out the pop up for a pickup and camper (or motorhome) then tow the boat.