Idyllwild is world famous for rock climbing and the parking lot at Humber Park fills up every weekend with climbers. There might be some market for a hostel of sorts catering to climbers. But be aware that climbers in general are cheapskates when it comes to lodging.
Idylwild is nice for a weekend getaway if you live in So Cal, but for full time retirement I’d say there are many other options in California and elsewhere that are nicer and cheaper.
