I'm presently a facilities engineer by trade, who does some construction and maintenance for landlords on the side, hoping to get back into the private real estate game.

Having the ability to offset their mortgage with an ADU would be a game changer. 

I have a few lenders who do but they still require some money from the borrower so they have skin in the game.  

Are there some of the data aggregation sites such at Deal Machine or Prop Stream that have this? 

Im not running a profit generating machine.  

This strategy can be a game-changer for building long-term wealth, as it enables you to leverage your gains without an immediate tax hit.Example: Sell a rental property for $300,000, reinvest in a new property of equal or greater value, and defer capital gains taxes indefinitely.5.

When you are new to the game, agents, wholesalers, other investors, and even you can push you around.

Collections are where the game is won or lost, and without proactive management, even the prettiest property can bleed money. 

Some/many lenders don't like a 2nd mortgage behind their first (like the skin in the game), however there are both bridge or permanent financing options out there allowing you to leverage anywhere from 90% CLTV - 100% CLTV, but don't expect good terms...

I suggest having smart TVs and let them log into their own accounts, preferably with a guest mode so they auto-log out after a certain number of days.For catering to families, I would concentrate on providing amenities like puzzles and games.