It's an interesting idea Don, but I think "making money out of your boat" should read "losing less money"

You probably need an organisation to go through the marina/survey/insurance questions - maybe Waterbnb? I'm sure it could work, but there'd be some hard yakka to get there.
I'm sure some marina complexes would see the benefits of a lot more visits to cafes, restaurants and other retail, rather than empty boats sitting there. Maybe they could charge a % or even act as agents . After all, many marinas have substantial charter companies operating out of their facilities.
Insurers are used to evaluating risk and charging the appropriate premium.
You'd need some certainty that boats used for this didn't require full commercial survey. Perhaps a self certified or quick visual in-water inspection to ensure basic safety provision could be introduced. A sort of basic, in-marina safety ticket.
How much for a night on a 40 yr old , 28 foot Compass?
Cheers
Bristol