Do you care about appreciation and house quality or do you just want "cashflow" properties? 

For example, when I buy a building in a "C" area, I renovate it to "B" or even "A" level quality.

Do some rentals just require the bare minimum improvements to get it rented or do someInvestors think it’s wise to go a little above and beyond in hopes for a higher quality tenant And better rent?

First, I think they would make the kitchens look a lot nicer and would in turn improve tenant quality / demand slightly higher rent in a competitive area.

@Jay Hinrichs and @Greg Dickerson, How can one find quality builders who will build for less than $110/sq. ft? 

In my opinion get a quality home inspector and pay them to go through.

I've owned and operated my welding business for 10 years now, and not having quality people in your corner, such as an accountant, can be pretty costly. 

It is unlikely you can build a detached ADU of this size and quality, not doing the work yourself, for $80K. 

- Is there a way to improve quality of the tenants in short term of 1-2years? 

Housing prices (SFH, MF, and apartments) all can vary depending on neighborhood class, size/location, time of year you're trying to fill it, quality of finish out, etc.