This implies 1) There will need to be market appreciation to be able to extract value via a refi or selling 2) It is cheaper to buy a property with an existing ADU than to add an ADU.

Properties that start cash neutral or a little cash negative quickly become cash positive at the first or second rent increase.  10 years down the road, they are very cash positive (assuming no equity extraction).These are not ordinary times. 

About half of our RE had all of our investment extracted via refinances. 

Propertyware has an open API so you can hire someone to extract the data you need.

I LOVE what Google has done to offer a simple, easy to use interface that allows for data extraction from Google Forms.

To maximize profits you need to extract maximum rent for the least input of capital.  

Not only extract value from your agent but also present your value in return.

if you are going to place it into an FDIC or buy toys with the extracted money then I recommend against it.  

We have purchases that now have rent to purchase ratios >4% ($16K/month rent on $375K purchase); imagine the cash flow if no money has been extracted!

I would probably think about selling it outright to extract the equity and buying 2 additional (cheaper) properties with the proceeds.