So I calculated an example. 20% of 352K is $70400 but there's also closing costs.

An ADU addition in a SFH zoned area in my market adds significantly less value than the hands of cost of adding the ADU.  

The one month's worth of rent covers some costs (cleaning, readvertising) and the rest is a hedge against vacancy.

Currently they are rented to 2 different mid-term rental investors = basically no management cost to me + no turnover headaches for me.

A house hacker with a  W-2 income can often times float some rehab costs on a duplex through cashflow or supplement some with their income.

So, by trying to get a tenant out and replace them with another tenant you have a 50% chance they will be the same or worse, plus the expense, lost rent due to vacancy, plus any tenant placement costs with your PM.

First year no PM cost.

DIY managing is usually best, so you learn enough to avoid getting taken advantage of if/when you hire a PMC in the future.Your challenge is learning enough to avoid lawsuits and costly mistakes!

The cost per unit is actually below average for Reno and maybe bit high for that location. 

If we rent our house out, the tenant would likely cover our entire mortgage, but our HOA costs are high (they were raised a lot recently).