Mike, just because it wouldn't make sense for you to sell a property owner financed doesn't mean it doesn't make sense for someone else. Once you start talking with motivated sellers the sky is the limit. I've been really surprised in the past about what I've been able to talk a seller into.
Example: I bought a 4-plex last year from a seller who financed me at 0% interest. You read correctly, 0%! every payment to him goes straight to principle. The really cool thing is that the term is for 12 years. I'll own the building free and clear in 12 years if I just make the agreed upon pmt (and why would I pay extra? You can't beat 0% interest, any where else I put my money beats that). On top of that the property cash flows after all expenses (utilities, on site management, repairs, etc). Which is all a bonus as far as I am concerned.
Point is, I would never finance someone at such crazy terms, but if your seller is motivated enough they might. I found out what the seller really cared about and I gave him that. Don't assume that sellers care about what you care about. A good rule for life and real estate investing is to give people what they want, and you will get what you want.
Hope that helps..