How does "autobuy" work?
Is it different than placing a WTB ad for a specific item?
My guess is it would be more technical than that. WTB's will float down after a while. Something automatic setup could stay in place until the user chooses to disable it.
Basically, if the database fields were setup properly, you could setup an "autobuy" so that if it saw the following:
MFG: H&R
Listing type: Barrel Only
Caliber: .22 Hornet
Price range: $100 through $150
Then the system could just register the sale unattended if something matching that criteria popped up.
The problem though, would be conflicting auto-buys. What happens when more than 1 person set up an auto-buy of the same item(s)? It would likely fall back to "first-come, first-served", and many people would still be SOL (PARTICULARLY people who register at a later date).
So technically, it wouldn't be all that hard of a thing to code, but I'm not sure it would solve much.