I I like to be in control  

in particular make sure you know the value that will be added by the ADU and that in your case both units may be rent controlled (no 15 year exemption in some jurisdictions for a garage conversion were garage is over 15 years old.  

We are considering developing it into a multi floor climate controlled self storage facility. 

It can boil down to human error and things we can control, but sometimes it is just an issue out of everyone's control. 

At least, find out who the company is and have them send over the bids to you so the company can't mark up.I also want control of the bank account, in my name.Gino

This strategy can help reduce utility expenses.Mid-term and short-term rentals can have utility costs up to 10% of gross income, including electricity, water, gas, cable, lawn care, and pest control.

This implies residential units can be built at lower costs and provide better return. 11) adding an ADU to SFH can make the SFH fall under rent control.  

I would like to avoid providing keys to the tenants and just have them setup and control the codes for access.

Nobody really knows how low they'll go but I agree with predictions of 20-25%...and I wonder what Agents are doing to make up that delta in their revenue.We diversified well in advance knowing we needed to create additional streams of income, ideally by simply focusing on what we control, the size of our roster, and more effectively monetizing all of our current transactions. 

At some point, people just say enough is enough.You have a lot of people on fixed income down there and the insurance increases are out of control.