Because ultimately this is a contract question... and to argue it at all would require the exact contract language.

The walls are thin and my oldest son can hear them arguing every day.

If the wording is such that you can't smoke at all, he could argue you signed the lease and agreed to the terms.

You seem to like arguing for the sake of arguing.

I'd argue that if you're buying in a high priced market, some inexperienced teenager who lives in his parents basements is even more dangerous to consumers.The fact of the matter is you've got to go to school for 6+ years to be a lawyer or an engineer. 8+ to be a Doctor. 5 year apprenticeship to be an electrician. 

Typically I don't argue with people on it, I just tell them to do it if they don't want to hear my points.

., while I clearly don't know your investment thesis, and I agree that nearly $34k/door, even for a fully classic unit is A LOT of money, I would argue that 2-3 month rent is generally not realistic in many markets, nor is that how I assess rehabs.Personally, I look at potential rent increase, i.e. can I get $400/mo in additional rent by renovating this unit

That 2.5% could no longer be a negotiation token that you used to have to make your offer stronger or put it in your pocket as a credit.I can argue that the pre-settlement was incentivized buyers to self represent because the industry had commissions available to the buy side. 

I could argue if someone is house hacking at 3.5% down then that is an even better return.

I would argue that it also depends on your goals as an investor.I love multifamily because you can scale much quicker with buying multiple doors in one transaction.