It has not been well maintained over the last 19 years with a string of just bad renters and the person I had managing it just didn't do good quality repairs or work to it. 

Well not literally, because all of that is handled online as well, which takes out the human element again.

For the house to be vacant for almost a year, I think she must not be well or be under some kind of stress, so I feel like by coming in and offering the right kind of deal, I would be benefitting her and myself at the same time.How would you guys approach this situation?

Ive lived in Thailand the last four years and have an opportunity to purchase a 30 year lease on a brand new fully furnished eco 1 bedroom at a beautiful tropical location that only gets busier each year.

Our Company has been buying notes for well over a decade.  

@Lance LvovskyCan you refer me to this person as well please ?

They are getting what they really want, and you are crafting the deal to where it will still make sense for you.One potential issue is if what is most important to them is also important to you.

I'm selling my house and want to understand the tax implications on the sale, because I have lived in it as well as rented out a portion of it.

The house is 55 years old, floors look well worn as if they are original. 

He will want compensation for doing the building and equity as well.