FWIW, we run an AirBnB out of our house. There is great value in that AirBnB covers things with a hefty insurance policy, they handle all payments, provide the back end system for reservations and availability, factor in applicable taxes (in many instances), etc. We have looked at similar services for RV rental. Those sites, too, have a fairly sophisticated web presence and back end capabilities. I don't know specifics but these things are costly.
I think the concept is a good one... just trying to present some likely cost outlays you would have to deal with. I suppose it could be done on just a forum basis but there may be some significant liability issues to consider. While we are talking about a tight community, we are also talking about (for the most part) strangers sleeping in people's houses. Many things can happen accidentally and otherwise.
Agree with you, Cabbagedad, my first thought was liability to the hosts and guests. That is why I believe making it a "membership club" would help in that regard as the membership fees would go to offset liability insurance costs protecting both hosts and guests. Regarding the back-end of the platform, I have that covered already as I was a computer programmer in another life...lots of caffeine, pizza and all nighters in my history.
You are only a stranger once...then you are acquaintances.
Concept still in infancy, however I imagine that homeowners would be there during the stays, so not so much leaving the dwelling wholesale to strangers. I think if the model works for companies like Air BnB, VRBO etc, then everything can be figured out/addressed and reasonable safeguards put in place for hosts/guests and exchange owners.
While the average distance from home for first-year freshmen baseball athletes is about 200 miles, that is an average and there are many who exceed that average. Also, other sports have much greater average distances. While we are all "baseball people," the concept would apply to a much larger pool of athlete families in different sports, thereby increasing the potential number of host participants who make lodging available. I quickly came up with the number of 600K athletes competing at the college level (NCAA, NAIA, JUCO). That's a pretty prime pool of potential hosts to populate the exchange with lodging.