Just a thought.... maybe a dumb one.... but....
Since you are down in Florida, have you thought about talking to one of the companies that create lania enclosures? Maybe they could create something custom that could be assembled and dissassembled.
Other than that.... trying to find a tent an open air tent like this one that is the right size for your ramp... which would be the least expensive solution.
https://www.lowes.com/pd/Ardisam-4-P...E&gclsrc=aw.ds