My wife prowls GC used constantly like a bloodhound looking for these kind of deals. She has scored several nice acoustics this way.
I will say that occasionally one of those deals has popped up, she jumps on it immediately, and the next day is told the item was already sold or there is a problem and they can't find the guitar. I suspect the mark down is for someone in the store location who works there and intends on getting it cheap. Under priced Martins. "We can't find that guitar in our store". Someone working the store hides it deep back in inventory and pays for it on payday when they have the cash. Those are just my suspicions but a couple guitars never showed for these supposed reasons. They were definitely hundreds under priced so I wouldn't be surprised. If I worked GC and could get dibs on all the under priced stuff I would do it.
I've often had the same thought - price something crazy low and stash it, then come back when you're off duty and snatch it up. I believe the store manager has to sign off on a price before it's entered into the computer system. But managers can be preoccupied and they might not pay much attention to used dealings; they're more concerned with new gear sales I think.
Have had a couple of unnaturally great online GC bargains denied the following day myself, after having thought it was a done deal.
We're not the only ones watching for underpriced items, of course; they'll sell almost immediately to somebody...
It is irksome that their system will process a sale even after an item has been sold or de-listed.
If that happened with new equipment they'd probably have to make good, but the rules are different for individual used items.
I did get a great price on a Lovepedal 'billet' fuzz, one of the handmade ones in a casing machined from a block of aluminum. I see these listed on Reverb for $300-500 used; got mine from GC for $99. I've been a big Lovepedal fan for years so it was pretty gratifying.
The two other GC deals I scored were even bigger savings.
In 2015 I saw an age-darkened Martin acoustic sitting off in a corner of the acoustic case. Took a closer look and it was an HD28 with some finish checking, obviously played and loved for many years. A few remaining strings were sitting flat against the frets. When I asked, the saleskid said it was only good for a wall decoration. He pulled it out for me and on examination the neck and neck joint actually looked straight & solid.
So I said okay, but at least give me a used case too. He went in back and came out a couple of minutes later with the original Martin factory case... I wound up getting guitar and case both, for less than the case was worth by itself. (Once a price is entered into the computers they don't - or possibly can't - question it.) It needed a new bridge & underplate and five new frets. Plays great now. And the tone is fantastic. Turned out only to be about forty years old at the time but it looks antique.
Then a couple of years ago they had mistaken a gorgeous Zerberus for a cheaper model and listed it online for about a quarter of what it should've been. I clicked through and bought it (including its formfit case) on the spot. Nice guitar, great deal.
Like I said upthread, if this had happened at a mom-&-pop place I would've pointed out the mistakes.
But in dealing with GC or a pawnshop, I didn't feel guilty about those scores.
They got what they wanted, and we both came away happy.
