What do you think the odds are that a strategy like this will survive the next economic reset? 

The majority of our expertise comes from experience and having a specific book of real-estate clients who are involved in a wide variety of activities.

But I am involved more in multifamily and hotel resort investing now.  

There's many other options in real estate such as syndication and note investing depending on your level of involvement. 

With online access to almost every jurisdictions property recordings, lenders today use software that automatically searches property transfers for transfers involving their loans.  

Leverage magnifies return. 3) The effort involved in adding an ADU is comparable or larger than a rehab associated with a BRRRR.

Going this route is more involved and that makes it more costly too.

Most value adds involve work   Some require specialized knowledge.Here is a list of why adding ADUs in my CA market is typically a poor RE investment:1) The value added by the ADU addition is often significantly less than the cost of adding the ADU.

The easiest of all the thing I've been involved in.

This will allow you to get the sheriff involved immediately.If you are already past the notice period then you will probably have to follow whatever state laws are in place for the notification period and possibly the eviction process.