Why is the price all over the place?

Looks like the standard chasing-the-market moves. 2007 was steady increases and the last 10 months has been chasing the market down.

Well I can understand chasing the market down. I don't really understand why sometimes I see the price oscillate...this listing is just an example. I've seen it literally be raised, reduced, raised, reduced in the period of several months. I wonder what they are doing? My best guess is that they are getting low ball offers so they raise the price in hopes that people are low balling only in reference to the asking price, thus a higher ask produces better offers.

Could be a broker's ploy, raise the price, and then reduce it back down so you show up in searches as reducing your price