As long as you have authorization from the owner of the property, you can post the listing on the website.

Your local housing authority will use HUD guidelines on the condition of the property.

I heard state senator Robert Wienkowski (author of many of the state ADU laws but I am not sure he authored SB13) discuss the intent of allowing unpermitted units (he used the word bootlegged units) being to not remove safe units from the housing supply.Seeing state law currently explicitly allows safe unpermitted units, a judge should not be able to rule otherwise.  

This is how most tax authorities determine value.

This part seems to impact broad authority in the Dillon rule state.

If we do all of the banking in LLC1's name, would listing the PERSON that owns LLC2 as an authorized signer pierce the corporate veil?

I have attempted to go in this route but am not getting a lot of help from the people that work in the housing authority. 

That's what the housing authority will use in your particular area. 

But beware of the downsides, such as strict rules, potential tenant problems, and dealing with the Housing Authority.

Was listing your property with a housing authority your first thought?