Duplex owner reached out to me for best offer

[Collin Smith]

Back in July I found a duplex listed on Craigslist in a desirable area of my town (Florence,SC) but after running numbers it just didn't make sense. They are 2/1 units, one is rented at $575 and the other is vacant because he is trying to sell and didn't want to hassle with finding a new tenant. Fast forward to yesterday (after it has been listed with an agent for a while) I get an email asking what I would be willing to pay. I need to run things through the BP calculator still, but my preliminary number is about $40,000 off of the asking price which would give me about $210/door cash flow with a 30 year mortgage on it. The current owner has had it since 1994 and paid about $15,000 less than what my offer would be. I do not want to insult but it needs to work in my situation, too. The other option would be to offer an own finance price with a lower down payment and refinance in a year or so to pay off the seller. A month ago I may have jumped at it, but now I am in sight of savings that will pay off my current home by the end of the year, which would free up a substantial amount on a monthly basis (we pay extra to get our home paid off) and buying this would probably put that on hold. If this situation makes sense to anyone, what would you suggest?