if you turn your garage into additional living space, make a plan for where all your garage stuff lives

This is a very LA thing. Garage --> ADU, and then once the construction is done you're like oh waitttttt where's all my garage stuff going to live? Make a plan ahead of time for bikes, tools, holiday decor, mementos, beach gear, baby gear and the like. Appropriate solutions include a large shed, a storage room built onto the side of the guest house, a large basement, a bike shed, etc.