I wouldn't want to sell using sub-to personally.  

At this point things do not seem contentious, and having a verbal dialog in person inside the rental unit might give you an idea of where you stand in getting your deposit back.What I mean is showing the pictures in person to the owner while the owner is standing in front of the place the picture was taken when you moved in well before you move out.Good Luck 

I bought a property through Miami Life Realty to ABC Capital Management with a loan from a company that I am not sure if it even exists, since there are many different companies with same name, but the address does not match anywhere and on the papers i've signed there is not any representative from the lender's company.

The advantages, in theory, are so huge and I'd like to know if they are true in real life:1.  

Be careful, since this is only for a Person and their primary residence, transferring to an llc may void this.  

I am an Akron realtor/investor that self manages but have out of town investors and want to be sure not to recommend this person to them.If you are ever in a pinch or need someone to pop by one of your properties let me know and I can try to help out.

What is my next step (what contracts etc do I need) without involving realtors so I don't have to pay extra fees to this and that person?

As far as your tax questions, I would personally refer you back to your tax advisor or refer you one if you need it.

A huge worry I have is now that he has a huge personal mortgage how would that even factor into the DTI? 

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