The advantage for utilizing this approach is not perpetual tax deferral.

There is no such thing as an agency contract that lasts into perpetuity, so there is nothing that is forcing you to work with your cousin.

It also seems to imply that illegal units will get amnesty (note an ADU law providing fed a 5 year amnesty on unpermitted units, but this seems to be a perpetual amnesty).Thoughts?

In other words the gentleman had more to lose than Phill Grove on that transaction.Each and everyone will surely have their own experience and there will never be a shortage of genuine individuals willing to steer themselves away from perpetual 9-5 until retirement, so there will always be Gurus out there. 

But you'd grab the business once even if it didn't come in perpetuity cause you see what's right in front of you, because that's how you're compensated.

What has me worried is that since the eviction process is taking so much longer, many are turning to other options such as cash for keys which dont end up on a tenants record.. they end up moving and doing the same thing with the next house/landlord and we continue a perpetual cycle of non paying tenants.

I am a long term investor (hold or perpetuity) so I am confident over time cash flow will slowly increase as will appreciation.

And, I would send notice of non renewal to the perpetually late resident, which is a judgment call based on my experience that late payers end up as non payers in many cases. 

Some just make perpetual threatening phone calls.Some start court actions, so they get a money judgment which they can use to at least garnish state income taxes (you can't garnish federal returns).Property owners need to start asking PMCs HOW they will execute their services, so owner expectations can be better met:)

Relying on perpetual home appreciation seems like a risky plan