My rents are high at $6300 per 3BR unit so I guess the risk is if economy goes south and no one can afford the high rents.     

It was actually affordable 2018.

Many people want to invest in real estate but can’t afford to buy an entire property or deal with the hassle of being a landlord.

Since you have flexibility with locations, you have your pick of cities that are growing, but also affordable.

In some markets you can afford to increase more and in some less.I raised my tenants rent by $15/m and they were ecstatic. 

@Priscilla C. how much can you afford to put down without tapping the equity in your current home?

This plays into the affordability issues for tenants by allowing them to live in nicer neighborhoods for less money, yet I get monthly revenue comparable to short-term rentals.

We're still seeing 1% deals here with positive cash flow at very affordable price points ($120k-$180k).

I maintain even break even on valuation (which is rare in SF Zoned areas), the ADU has big disadvantages versus new property acquisition including financing, level of effort, rent control, prop tax being based on cost rather than value added, length of time including length of time from first expenditures to first income, reduction of something from existing unit (in your case existing home lost its garage).Did you see starting next year Mf can add an ADU per unit up to 8 units without any affordable housing concessions?

Studies typically cost $3,000–$5,000 but affordable DIY options (around $400–$500) exist for simpler properties.