I don't go to many auctions, but do go to a lot of gun shows and stores that have used guns. Can't remember seeing a .257 722 at any of them priced for less than $500 for several years now, and often they're around $600. They also seem to sell at those prices--or at least when I go back to the same store, or attend the next gun show (where many of the tables are rented by the same people) they're gone.
One way many people gauge the going price for various firearms these days is Googling. Some of the results will be "asking prices," but some will be selling prices at various on-line auctions. I just Googled "Remington 722 .257's for sale," and came up with five results from the past two years ranging from $450 to $700, averaging $542. And the $450 was for a barreled action only.
You're obviously free to judge what you think a rifle is worth, and bid accordingly. That's the way to get bargains, but the market for this model has gone up recently. My web search did find some older results from as far back as 2002, and they were in the $400 to $450 range. Buying one for that price would be a really good deal in today's market. Obviously you don't "need" one so can afford to wait.
