Selling a home without building permits
I'm in NJ so it might be very different in California. If the wiring was done to code and was done by the homeowner there should be no problem. The sheetrock in the garage is code here now. So updating the garage to reflect that should not be a problem. Here's how I would handle it here, it was done over a period of years, a little each year as finances allowed. The seller will probably hire a building inspector to check for any deviations from the code. It might be a good idea to get your own to do a run through first. In NJ and our Twp a building permit is based on the expense of the project. Minor projects usually do not require one. Good luck!