At this price the model year and miles would not be my main concern,,, the test drive and mechanical inspection would decide my further interest.
When you go for the test drive, here is a link that will give you a few pointers what to look for
http://www.usedcartips.org/TESTDRI.html
If vehicle should still be of interest after the test drive, the $110. independent mechanical inspection will be peace of mind,,, I assume with the cost of this inspection it includes a compression and diagnostic check- Up ?
The seller is asking $3200. and you want to offer $3000 - $3100.,,, sorry to say, shows me you got no clue how to start the negotiation process,,, you start at $2500. and work your way up slowly,,, this is really an area that can branch out as to what is a fair paying price " example " suppose the mechanic says the vehicle will need $800. in repairs to make vehicle 100% road worthy. " what will now be a fair offer ? "