This comes from a 2017 City document, but it seems to be current.http://www2.oaklandnet.com/oakca1/groups/ceda/documents/report/oak050966.pdfA real pity, with the severe lack of housing in Oakland. 

Verifying last 2 years of rental history very important!

Any good HML will be happy to share the contact info of borrowers so you can see how easy the process was and how well they treated the investor.Can you share a recent closing document or HUD?

But, people will always be able to see the prior listing history under the Price History section of the listing.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

Platforms like Zillow or Redfin can give you insight into comparable properties, and PropStream is great for deeper analysis like liens or ownership history. 

First, I’d check the sale documents and listing details to see if the property was explicitly marketed as a triplex.

Verifying last 2 years of rental history very important!

Alternatively, you may want to consider switching to a platform that offers this level of transparency.Additionally, on both Airbnb and Vrbo, if you have access to the account, you can view the transaction history.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?