I don't see the difference between what you propose and AirBnb. Also, I'm not sure I would use an on-line B&B service when I can use couchsurfing.org and warmshowers.org.

I might use such a site if a) no free hosting was available and b) no motels were in the area at a comparable price. If the prices were close, I'd rather stay at a motel than someone's house because it is much more hassle to stay in someone's house than at a motel.

In fact, there are times when a free hosting is possible, but I choose a motel anyway because I am too tired to interact with the host.

Frankly, I see it as the worst of both worlds: it isn't free and I still have to observe all the niceties in someone's house.

But, good luck with your endeavor.