There's more to it than that because Fair Housing spells out some very specific groups you can't discriminate against but there's also this little thing called "disparate impact" that must also be considered.

Let's say I upgrade my HVAC to replace old if install new condensation units worth $10000 just for the sake of numbers, how does it impact my depreciationWhat section of tax returns has information about depreciation.Appreciate your inputsThanks.

It also imposes a steep fee for demolishing an existing structure.While the impact is debatable, if you are considering any address in this district, chances are you will be allowed to establish a second unit by right”.

I do have the time to do a ton of research, but of the two links I clicked on (told you I didn't have  lot of time) this Pew report seemed interesting, it is four years old, so COVID has had an impact, but we can roll with it. 

Inquire about the impact on the properties from the most recent flooding in the area (Dec. 2015).

That will have an impact on your cash flow.  

However, like @Russell Brazil pointed out, there mostly likely is not another RE bubble around the corner and whatever bubble is out there will not have a dramatic impact on RE prices, at least nationally.

If so, what impacts do you think it will have over your long term profitability investing in markets with weaker demand and greater supply relative to that demand?

Very generally speaking, does the fact that another tennant would be sharing the property negatively impact the amount of rent  I can collect on the main 3/2 - if so how much?

Bill and Kim will never know the impact they’ve had on our lives.