Seeking advice for buying from retiring landlord

[Chase C.]

Hello BP--

I got my first driving for dollars/direct mail call back on a multi-family property in Fredericksburg, VA. It's an exciting first step, but also a little daunting, given that I've never closed on a deal before.

This would potentially be an off-market deal, but the seller isn't motivated by any financial distress--he's just looking to start unwinding his portfolio.   I'm wondering if anyone has been in a similar situation, how it turned out, and how they determined their absolute max, walk-away-from-the-table price.  This is a fourplex that's assessed in the county appraisal district at 340,000 and the owner claims it takes in 925 per door.  (I've gotten pre-approval for 300k, so that's my top dollar for now).

I would value any advice or insight.  

Thanks, all.