Looks like they forgot a "1" in front of the "2,900".
You feel silly not calling just to see if perhaps someone doesn't know what they're selling, but it is far more likely that there is a scam somewhere in here.
In the end of the day, my concience would have a hard time buying "Dead Grandpa's" tractor off of "84 Year Old Sister" for that price just because she doesn't know what it is. If that is indeed the case, I would give her $4,400 though she is asking $2,900 and consider my self the luckiest guy around.