Once the flow starts you just have to keep it moving.

Beyond that, I am intrigued by the possibility of building a portfolio of small multifamily properties and generating cash flow to increase my flexibility and time with my two young sons.  

Now converting to rental for a positive cash flow of $1500/mn, continuing to build portfolio, and developing land home sits on (zoned for 40 units).  

Sounds like you have lots of room to improve cash flows though.

Monthly cash flow could be a problem.

We are primarily looking for long-term buy & hold rental properties with good cash flow.  

If you have money to make the property cash flow now with an acceptable rate of return, go for it.

If you pay for water you would be better off spending the money to split the utilities and have the tenants pay than trying to save water with low flow toilets. 

I figure if I can average buying 2-3, do the necessary remodel work (ceramic wood-look floors, white semi-g-gloss walls..basically renter-proof the house) and hold it long term that in 10-15 years I'll be paid off and have great cash flow to retire on.My amateur thoughts are and keep in mind this is my limited guess on the oklahoma marketplace is:buy house 60-80K. invest 0-15K remodeling and simplifying the home.

At this point I can tap bank loans for much more favorable terms so I should probably hold off on any seller-financing deals until that no longer becomes an option.Overall, the deal seems lose/lose.  12.5% locked in for that long does seem like a low ROI for the seller (especially considering interest rates will likely rise significantly in that time), yet still too high for me for cash flow purposes.