As I wrote above I own quite a bit of time at the Westin Mission Hills in Rancho Mirage, CA (in the Greater Palm Springs area).
As for the concern about what if "guests trash the place" this is not an issue since Mission Hills is managed by Westin (a major near luxury brand that is now part of Marriott). If the guests do "trash" the place Westin will gladly charge their credit card exorbitant amounts to repair the damage and they have extra furniture and fixtures in storage for this situation. Also at this price point it is less likely to happen (but people with money can act like idiots too).
Now if you own in an old school timeshare where there is not the management infrastructure Westin brings it could be a different situation.