Would it be helpful to connect on a call and talk through details of this property and laon types? 

@Jeremy TaggartThank you some much Jeremy for the detailed answer!

Need more details. 

What about something like this: https://www.realtor.com/realestateandhomes-detail/3032-Glenm...?

.: Someone asked for more detail on Creative Finance.

Use a servicing company, you don't want to be tracking that yourself and worrying about the details.

Verifying last 2 years of rental history and income extremely important to find the “best of the worst”.Make sure you understand the Class of properties you are looking at and the corresponding results to expect.The City of Detroit has 183 Neighborhoods we’ve analyzed.DM us if you’d like to discuss this logical approach in greater detail!

The guru your son is learning this technique from is likely not telling your son that the deal will almost certainly encourage your son to get an "off-market" deal from a "wholesaler" who is unlikely to properly disclose the details of the property or encourage an inspection. 

Speak to a Realtor or Appraiser: Get a more detailed estimate of what the property could sell for with and without renovations, as well as its potential value after adding an ADU.

If you would really like to explore the sector : why not go and message 10 to 20 operators and offer to look after their property or clean their property for a month in exchange for their knowledge and details on the numbers.