This is a $2100 upfront money grab from what appears to be a payday loan company.

Keep in mind it is usually not cheap or 100% effective.

This would imply AA has an effective tax rate of ~3.5% for an investment property 

If your 401K is with your current employer, it is (effectively) impossible to make it an SDIRA. 

It's effective interest is similar to Mezz-debt at current rates but a bit lower.   

I recently completed one on a multifamily property and found it to be a cost-effective approach.That said, there are a couple of additional factors to consider beyond the code differences between a garage conversion and new construction:Coastal Overlay Zones – If your property is in a coastal overlay, building a ground-up ADU may require Coastal Commission review, which can add time and complexity to the process.

Just Gen-Z; don't you think all Gen's might be effected by these same forces?

You know, one of the most effective ways architects can help real estate investors is by using smart design to boost returns on investment.

The conversation covers issues like the impact on property values, tenant rights, and the broader effects on the real estate market. 

I believe addressing the root cause will be far more effective than having two different property management companies trying to manage under one roof.