Garage to ADU Conversion

I have an existing detached two car garage with a large attic space. The garage door has been replaced with a wall containing the double doors and two windows several years ago. I want to add a bathroom, kitchen wall and stairs to a loft bedroom to make it a self contained rental unit. I would like to move the main power connection for the property to the garage. I will connect water and sewer to the existing service for the main house. This ADU is located in the city of Los Angeles.