If it works for you then cookie cutter it and keep doing it and be happy. 

Sounds like they rigged rooms without legal permits.

So, they are cookie cutter with strict and exacting requirements.

Are there pre-published cookie-cutter plans I could buy and then provide to a builder?

What does the local competing supply/demand look like for the price range you are proposing.Are there "Target Demographic" buyers in the area, or will you have to attract them there.Do you know what the "Target Demographic" wants--Cookie cutter McMansions or highly individualized residences.

Thank youWhen you say "truck driver" does that mean you spend a lot of time away from the property for days at a time sleeping in our rig?

It would depend on the neighborhood and the renter types in the units above, as well as the risk of longer time on market compared to a Greige LVP cookie cutter apartment.A DIY would have a lot less money in it to risk.In a B area, maybe something like this (maybe--maybe not though--risk).Just some food for thought.Like a sports bar, with a black drop ceiling, water resistant LVP, and hide the sewer pipes in a closet. 

I'm not like a lot of the other volume house flippers around here who are doing a dozen deals at once and slapping a bunch of cookie cutter builder-grade Home Depot finishes in their projects.

As a result, they will not go the extra mile to work on a somewhat complex scenario, since yours does not fit into the typical cookie cutter box.

If you do use SB, cut the pipe with a tubing cutter only and sand with plumbers tape.