In your situation, I do believe the best temporary option for you is Cds..

You stated it was a nice family, what constitutes a “nice family” and was it an emotional feeling about them or primarily a numbers thing (income, debt, job security, etc.) or a mix of both?

Random people have walked in the back of the unit and the tenant is demanding that I put security windows or else he will file a lawsuit with his lawyer for unsafe living condition and emotional distress if I don't do it. 

I screened as well as I could, they all looked good on paper, seemed nice in person, references and background checks checked out etc. but turnover was higher, living there was less fun, and a few house mates turned out to be nightmares: one started working as a paralegal and spent her days researching ways to screw me over on everything, another one started secretly growing peyote in his closet and ended up trying to stab another housemate who drank a bit too much one night and got emotional when I was out of town (they both spent some time in county jail over that incident and had to be asked nicely to GTFO) another one lived almost entirely off of expired frozen cod that he bought on sale for $1 and then microwaved it, making the house smell like nasty rotten fish for a few hours every night... barking dogs left unattended in the yard, dog fights, angry neighbors, dog poop, the peyote cult coming by and hosting drum circles into the night having bon fires in the yard, police coming by, fire department coming by... ...my future wife moved in and then we moved out pretty soon after, bought a different primary with no room mates, kicked all the crazies out and made it a normal rental rented to a family.

Just don't get emotionally married to any deal.

They politely pointed out that the contract allows the seller to back out.So, needless to say, I'm running through a range of emotions - disappointment, perplexed, angry, and just p**ssed off. 

It is a mindset that focuses on making more money and not indulging in emotional spending (fancy car, Starbucks, etc.) 

Combine this with the intensely emotional aspect of home purchases for 98% of consumers, and you can see why people are reluctant to hand this over to an online process, even if it would be more efficient.I envision a future where realtors are more hands off and manage more and more listings via online portals.

Most new investors bail on investing because they run out of steam--emotional momentum if you will.

Don’t get emotionally attached to the deal just because it may be a good one.