[lordfa9]

I usually follow up with the seller to find out what he ended up trading for (it surprises me how many don't mind telling me). Usually it's just a little bit above what I was offering (mostly but not always in unusuals). Probably about half have buy-out prices listed. I also check the last owner's trades and start offering at (or maybe a few keys above) what the current seller paid (it's usually easy to find this trade because most of the time it happened within days of the seller acquiring it).

odds are he told you that if you had only offered just that bit more earlier he would have sold it to you

tradejacking is fair game, get used to it