This has to be the oddest auction I've seen in a very long time. If the seller doesn't want to sell, just pull the auction. The only thoughts I have are that he hopes someone will bid to lock in before the price goes up, or maybe that it is necessary to boost the starting price to ensure the final value gets where he wants it to be as the auction end approaches.
Olie, it seems that the power supply and cable were added to be included as one of the updates. I know that if I were watching this auction as a potential buyer, I would be completely turned off by the antics. A stranger might be hesitant to put thousands of dollars at risk to make a serious deal with such an apparently flighty individual. Too many changes to the auction and who knows what you're actually going to get? Well, to each his own. Maybe someone will be interested enough to bid, maybe not. I know that, if I were willing to pay $5300 for the bass, I would have placed a bid by now to lock in the price based upon the increases.
If Hal really was willing to sell it to a club member for $3500, I think he would have chimed in or posted it here, particularly when multiple people expressed interest. If you're one of the interested parties, then figure out how to email Hal, directly or through eBay, and see what he has to say. While I would be scared off looking at the auction as a stranger, I wouldn't be afraid to deal with Hal directly.
Here's hoping that, one way or another, the bass finds a good home.