@Jake, I would assume he means taking them down cash then selling to another buyer who is either all cash or financing. In either case, if the deal was a great spread back in the day, it would have been easier to sell via wholesale in the same condition to another rehab investor back then. Today, the spreads are not there so that is almost impossible. (I did say almost)
@Jeff - Foreign mula could be one of the reasons. A second is the speculation investors. They feel that CA prices will likely increase and when they do, at a rapid pace, therefore, they are willing to pay these lower spread, higher prices, rent and hold for as long as it takes, taking negative cash flow along the way until that payday comes. Certainly a strategy, but not one I would apply personally.
Lastly, with the high exposure that trustee sales have received in the past 3 years and all the flip shows on TV, there are so many rookie investors out there who pay more than they should and this is just another reason why the spreads are thinner, not only at trustee sales, but at MLS listed REO's as well.