HelloI’m currently in the process of selling a home and am under contract to purchase another home using 1031 exchange.The home I’m selling is under mine and my wife’s name personally.

Best to start the process to sell.If you decide to keep it, you should talk with the contractors - you don't need to do high-end renovations for a rental.

You can write off everything still, its actually better if flip takes more then a year as you can make it look like a long term capital gain, need a investor friendly CPA who isn't afraid to do what gets you the lowest tax payments. 

I want to point out that I’ve noticed his tone in emails can come across as demanding or even a bit rude.For examplez: I see how he writes to the group—always polite and full of "thank you"s—but when addressing me, the tone feels far more demanding.Would it be okay to respond with something like this?"

Many investors do this and don’t see issues, but it’s best to proceed carefully and know there’s some risk.You don’t necessarily have to inform the lender, but it's wise to consult a real estate attorney or CPA to guide the process and minimize risk.

In Metro Detroit area, police will not remove these types of occupants (they are afraid of scamming landlord having police remove legal tenants), calling them a "civil matter" forcing landlord to start court eviction process.

-repeat the process every year by acquiring one house every year with the appropriate income qualification

The appraised value seems low and I am trying to understand the best strategy to challenge this value and the cost / benefit of going through the condemnation process. 

Just consider the rent you saved buying the place as part of the profit plus any/all the write offs you’ve had for 3 years. 

Due to item 1, adding an ADU can require years to start achieving any return (once the accumulated cash flow recovers the initial negative position).4) Adding an ADU is a slow process.