A professional is someone that conforms to technical and/or ethical standards of a profession.

I called every facility in my market, introduced myself as a burgeoning investor, and asked if they would consider selling.

Ive taken over standard mortgage companies before sub to. 

Investment properties typically require at least 15-25% down but at standard rates. 

Someone who is willing to seller finance may be willing to offer terms  for a low down payment option but that will come down to negotiations since there are no standard rules for seller financing. 

Is there any standard paperwork I need to sign with a troublesome tenant who, after long negotiations, moved out on time?

This does not seem standard to me, and maybe illegal?

We go down to a 75k value/purchase price for example and some of the same tests that a loan this size may fail for a standard mortgage would not be an issue. 

Sorry to hear this.I would always say that "There is nothing wrong with any property as long as the price is right".Granted, some are not salvageable and the deal doesn't make sense even if the seller paid to me to take it lolOver the past 10 years I have witnessed many investors trying to do the same thing as you.Purchase from afar without buying turnkey and trying to do it themselves.This has been popular especially the last few years.Not many succeed unfortunately or they don't succeed in my eyes as they are into deals for much more than what they should be.There is a big trend going on where folks are made to "feel involved" with the purchase, rehab and property management process.The properties look great and off-course they do as rehabs cost $40,000 - $50,000.It doesn't sound like a lot of money for folks from CA and NY but for our local standards it is and IMO kills the cashflow and is unnecessary overcapitalization.Each to their own I guess.Just had a call the other week with a fellow from CA that bought a few turd properties from a local scam artist and is flying to town to try and rehab them himself.Another fella I managed to save even tho he lost his deposit of $1,000 as the seller (Another known scam artist) made him commit to the deal without allowing an inspection or even a walkthrough...If that isn't a red flag then I don't know what is 🤷‍♂️Hat's off to you for flying into to town to see the property for yourself.Wishing you much success

Please be gentle; I'm new at this and it's pretty complex :)Structure / Legal Details- we'd establish market value through a combination of comps from local real estate agent and an appraisal- attorney would establish all required "arms length" aspects including a mortgage at a minimum standard federal rate- LLC would pay us back based on a standard promissory note over 30 yrs Pros of selling to the LLC (I think)- A sale now would be the only time we'd be able to take advantage of the cap gains exclusion on this house bc we won't qualify for the "live there 3 of 5 years" rule due to the timing of our lease and our last time of residence.