Building an ADU is hard, difficult to get financing and city will hold you up with permits.

The only permit requirement is for sewage treatment.  

No square footage was added, so I didn't pull any permits.

Both FNMA and FHLMC permit this, under the following circumstances: Notes: For all such transfers affecting mortgage loans purchased or securitized by Fannie Mae on or after June 1, 2016, the transferee is not required to occupy the propertya limited liability company (LLC), provided thatthe mortgage loan was purchased or securitized by Fannie Mae on or after June 1, 2016, andthe LLC is controlled by the original borrower or the original borrower owns a majority interest in the LLC, and if the transfer results in a permitted change of occupancy type to an investment property, such change does not violate the security instrument (for example, the 12 month occupancy requirement for a principal residence).The servicer must notify the borrower that a property transferred to an LLC must be transferred back to a natural person prior to any subsequent refinance application in order to meet Fannie Mae’s Selling Guide underwriting requirements.Citation: D1-4.1-02: Allowable Exemptions Due to the Type of Transfer (04/13/2022)Now, you will still have the Note and reporting in your name individually and will still be personally responsible for the mortgage and most likely, the manner of transfer will enable any litigant to pierce the veil of your LLC, but you'll have what you wanted, for whatever reason. 

Engineer and architect to verify buildable and permits able to be pulled 

In most places you can only do work requiring a building permit if it is your primary residence or unless you are a licensed and insured contractor. 

Protected series requires that the LLC certificate of formation must provide notice of the series structure and the LLC agreement must permit the formation of different series.

And what permits do you need from city?

If this is a relatively small project, then you can ignore the rest of my post.If we're talking a big project, like at least mid six figures, you will probably need architectural drawings first, and permits. 

@Presley Becker visit city Building & Assessing Departments to see if any open permits or tickets, or recent history.What are city requirements regarding inspections and registrations?