I have a choice to make on which lender to go with on my rental property refinance, however as I research each lender, I cannot find adequate information about their actual business practices. A few I found some infor...

Offer cash for keys to person but money is only after they leave and property is left in broom swept condition3.

I would suggest that you not concern yourself with minor situations, as that is why you have hired a PM.

Whether that be starting the side hustle of real estate investing, or finding a new job, but, personally, I would not suggest you leave a well paying job until you have started down the path of real estate investing on the side.

I'm the buyer offering them the chance to rep me on the buy and the sale once it's built/renovated, so it's an easier sell, but if you can figure out something to benefit both them and you, it should workout

I gave an offer but doubt it will be accepted.

In hindsight, I should have purchased sewer insurance right out of the gate (if they offer that where you live) or at least, had the line camera scoped so I could see what it looked like.  

I would also suggest reviewing your lease with your Attorney. 

Purchase price: $200,000 Cash invested: $15,000 Sale price: $260,000 Purchased a cosmetic flip, invested about 8k in repairs, and a couple thousand for using a HML, listed on market and received multiple offers all above asking price.

It is rare for the "actual" (a note to the military as the unit leaders are "actuals") to offer one on one.