My question involves towing laws for the State of: California

My spouse went to an apartment complex in California to visit a friend. He parked in an area that seems to be open parking. Even the tenant said it was fine to park there. His car was towed away and of course a ridiculous fee to get it back was requested from the tow service. They claim the manager of the complex requested his car be towed away because he was in another persons spot. There were no signs posted in the open where he parked NOTHING! The only sign stating private parking for tenants only, was posted under the building where you would need a card or code to enter. After disputing with the tow company, they claimed there are no signs but when the complex put them up, people would pull them down! This is not our fault. The Complex can paint it on the wall if they have a problem with sign removal! Or continue to make sure signs are posted accordingly. What are our chances of getting back our money? And from whom should we demand it?