It is harder to sell on the back end, but I do feel like it is easier to negotiate nowadays.

I can only think that this grows as we move into the typical buy/sell season.I assume that your buyer funnel is full, and a lot of people have the want to buy with a constraint or two (rate mostly) of some sorts and you're working with them to execute their purchase at the right time while working around their constraint.

I am not seeking to charge each tenant, only seeking to remotely monitor each buildings water usage to identify costly waste/problems early as possible.

Ladder them up so they sell at different times so you'll always have cash flow coming in. 

Meaning, you have to always be selling, always doing your best for a 5 star review.

Not here to sell anything.

Yup, this is exactly the reason that I wouldnt allow delegated correspondent - it's too easy to get greedy and gloss over red flags when you get paid to package and sell risk to your partners instead of bearing it yourself.

Sellers cannot sell so they convert them to rentals.

Of course "hoping" rates will come down is not a sound strategy so finding a way to assume a loan that already took advantage of low rates is a great option.If you were starting over and targeted a large SFH, would you try to maintain the property in a way that would still attract regular homebuyers (not investors) if you needed to sell?

Then, give each account a name that can identify who it belongs to.