I like the location and the price is 650kHey Max, you are referring to the old Gem building.

You can create a website in seconds nowadays but I would also provide him a pitch deck to show how this works and that he is not going to have to evict you in 5 months because payments are not being made. 

Do you check Landlord references?

To give you something as a reference based on your budget (30-40% down with $1.8M), the general cap rates you will see in the Bay Area are roughly 3-5% https://www.loopnet.com/Listing/1047-Rich-Ave-Mountain-View-...https://www.loopnet.com/Listing/1180-Saranap-Ave-Walnut-Cree...You will find higher cap rates and more 20+ units buildings in SF, Oakland, and Richmond, but keep in mind of their stringent tenant laws. 

How accurate are websites like Airdna?

Through the HUD website How did you finance this deal?

And now a Zappa reference too.

Also I am referring to a single ADU on a SF zoned lot.  

I know you can look at various websites that will give you overall rental stats for a certain radius. 

However, when I reviewed the property information on the PVA website, the records indicate it is a 3-bedroom, 2-bathroom property, excluding the 2 bedrooms and 1 bathroom located downstairs.