The other problem is I am not totally trusting the "...finding out how much they will be able to pay..." part how it can really be established. 

Truthfully over a short period of time it doesn’t move the needle much on investments under $100k.Clearly your better half is much superior to you in every respect.

On the other hand, if the video reveals that they have been a little less than respectful of the property and you see a lot of maintenance and damages, just keep on shooting.

I would suggest working with them, as most tenants will still be reasonable human beings as long as you treat them with understanding & respect.

I can take 75% ARV loan or I can take 50% of it and as result have cash flow either 800ish or 1200 respectively (tax and insure included ) 

I respect your opinion.

Basically, I just asked that they respect that the shared kitchen and living room were integral parts of my home too, and that they refrain from being overly intimate with one another in those spaces.

Anything collected after closing is yours, so I would insist that you keep the 5 days of rent and not have to give it to the seller after closing.You need to establish on the first day you own the property that they need NEW leases and deposits, that the pets are not ok (or are with a fee if you want), and be strict. 

Hit your network of friends, family, and service providers (your CPA or estate attorney might now folks with cash to spare looking to park it in real property during these times).This is one of those times when having networks of people who know what you’re doing and already established is super helpful, but if you don’t have those, then now is the time to start building them! 

If you haven’t, I have a close connection with an established home inspector with over 25 years of experience in Rhode Island and Southeastern Massachusetts.