The owner of the property is highly motivated to sell, tired of dealing with his tenants, heading to foreclosure and looking for debt relief.

What in your opinion is the seller's true motivation?

I keep saying this over and over, you should be looking for motivated sellers and private lender money all day long.

I can either teach them something or I can learn something from them, or we can work together and do business or we can just motivate each other. 

A LOT of motivated sellers are willing to consider doing this for you.

Im definitely motivated to get started but what should i do ?

I am a former student of Mark Podolsky and his Land Geek land investing system.I have since branched out to form my own free private Facebook group called "Land Motivation" which is made up of many of Mark's former and current students as well as others who are actively flipping and wholesaling land using his and other similar systems.To answer the original question of this post, I have not bought land from Mark or his Frontier Properties website but he is definitely legit and all of his students (including myself) are following his land flipping formula or some variation of it.

It seems they'd be the most motivated of sellers to work with.

I'm not sure how you'd pass those through without a partnership return, or even if you can do it on a partnership return given that a partnership is supposed to have a profit motive.

If I were to purchase a property "subject-to" from a motivated seller and 6 months down the line the original owner wants to purchase another property that he/she will be occupying; how difficult would it be for the seller to qualify for a new 2nd loan on a new home being that they still have a first mortgage attached to their name?