How do i go about getting my security deposit back in CA?

So i rented a house in CA for a short term 6 month lease. The agents who i rented the house from did the walk through inspection before i moved in and that was that (no paperwork or anything). This is the first time ive rented in a while so i was unaware this was the norm. During my 6 month lease various little things would break (doornobs, oven, cabinets, fridge, etc)every time i called the landlord to please fix the essentials the guy would come over himself and attempt and i mean attempt to repair. Seeing it was a short lease i gave the guy a break and didnt really bother him the last remaining months. Now before i moved out he came over to do an inspection which i thought was going to be a very easy informal matter of business as i did nothing to damage the house. Anyways the guy gives me a LAUNDRY list of everything that is wrong with the house. Mildew in shower room (carpet up to the shower), mildew of the boards in the same bathroom. Scratched floors, dead grass, nails in the wall (i didn't hang one picture there were hundreds of existing nails from the previous renter i guess). seeing this list i knew the guy was going to be a problem i had both Realtors come over to inspect the house which they both said it was fine and in the same condition i left it in. The landlords realtor even said that the landlord has done this in the past and she was very sorry that hes such a problem with the deposits.okay so on the 22nd day after i left the property he mails a letter which is marked on the very 22nd day saying hes keeping all the deposit money for the previous things i listed and is even demanding more! what should i do? im thinking about filing a complaint against the realtor fro not disclosing this info. im also wondering if its against the law to not do a pre move in walk through?? it feels like this whole thing was very calculated and i rented from some scam artist HELP!!!