The buying mentality on an online auction site isn't soemthing that's necessarily described as "sane" sometimes.
People tend to get caught up in the heat of the auction and even outbidding themselves, paying more than they intended. It's similar to gambling in that respect...people can get caught up in the action.
I was attempting to bid on a Marlin 783 bolt action .22 WMR to replace the very first rifle I bought when I was 18. (Mine was stolen a number of years ago.)
Marlin makes the modern equivalent (XT-22MTW), but it has a new trigger type that I'm not yet certain I want. The Pro-Fire Trigger has a built in safety that has me giving it the evil eye.
For a Marlin 783 in excellent condition, I would be willing to pay a bit more money than for a new version, just for the sake of having the 783 again. I found one in said condition starting for about $250, figured I bid a while and see what happened.
The price soon soared over $500. WAY in excess of what I was willing to spend.
I love that particular gun, especially for the sentimental value. However, realistically speaking, paying more than half a grand for a rifle I can easily buy two of brand new kinda puts the kibosh on the sentimental value for me.
Now, had this been at a gun show or a private deal person-to-person, I'm sure I could have gotten a better price because there wouldn't be any bidding to get caught up in.
Perhaps I'm wrong...but whenever you buy something via online auction, I don't believe you're necessarily going to get something as what the regular market would do for you. This means you have to be more careful not to get caught up in the heat yourself and to practice some patience.