This is where you need to get creative. You say a hoist is out of the question because of height ... but can you properly anchor some rings? If so, you can use ratchet straps to start lifting one side. I'd go out to a home improvement store and look at damaged pieces of insulating foam sheets - 4x8 sheets ... here, if they're cracked or missing a chunk in the corner, they sell them for $1.00 - $3.00 ... Get a few set on the floor so that you're not rolling the edge against concrete. Ask a flooring company for some long narrow carpet remnants and use those to protect it, too ...
Get those straps up through the rings and hooked on the boat ... maybe 5 or 6 ratchets on one, move down to the next, then the next, then the next ... and then back... Depending on the boat, you might make some wood cross members to run at the rub rail level of that hull so that you don't get too much flexing in the flip. I'd say just start. If you find out it's not going to work, at least seeing what's happening while you try can maybe give you another idea.
I've had to do nearly everything myself, too. The nearest member here is a two hour drive away. I'm in a small town and geographically isolated, too. Worst case scenario to what I suggested above is that you spend a few bucks on rings to anchor on a ceiling joist and discover there's more twist than you can overcome and you have to lay it back down. When I lifted my deck (certainly smaller than your hull, but still alone and under a 7' ceiling height), I used ratchet straps to get it up & then made myself a rope harness to lower it back down - this way I could release the ratchet completely while holding the rope and slowly letting it down corner by corner.
