If they have permission from the previous owner, no adverse possession.Its continuous for the required period. 

One of the ways Seller Financing can be most valuable is if you can get the Seller to agree to either an A) low interest rate, B) low down payment, C) flexible timeline options (no interest for a certain period, payment once you get other deals in the pipeline, things like that).

We have already increased our knowledge through all the great information available here on Bigger Pockets and look forward to continuing our education.   

Or would I have to wait a longer period of time before I could get rid of the house?

Well my partner @Kevin Moen is a Note School alumni and has done very well from the education he recieved.

I can tell you that despite some vacancy periods over the last 7 years (and one that lasted about 8 months one time awhile back), they are all very much cash flow positive.

I have used airbnb to see the interest for  potential vacationers for a 3 month period but it doesn't seem to get much attention.

Things like taxes, etc are no problem but when I do my periodic walk around our city and spot an unkempt house/apartment building how do I tell if the owner is well positioned for self finance, etc? 

I was wondering what websites, blogs or periodicals you read to learn about what markets to invest in or about the state of Real Estate in general, or specific markets?

Network and learn as much as you can from others, educate yourself, select a market, pick the niche where you want to play, and go for it.