bidshares is a direct-from-owner site, much like vrbo, AFAIK.
The reason skyauction is down is that available inventory generally in RCI is down. Orlando travel has just picked up, and so there are fewer fire sales to be had. You can still get stuff last minute, but you really have to be thinking last minute---six weeks or less.
I listed my New Years week at Mystic Dunes there last year, but didn't get an acceptable bid. I sold one timeshare using the site a year or so ago, but they don't seem to get a lot of action.
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