Stephen, that is a hefty charge to ship to San Diego. Doesn't make sense it as much as it costs Garry to send his car to LA from Australia!
To avoid brokerage fees, you should see the cost from Buffalo? I have found the transport brokers post your car and the independent haulers bid on your car. I found it fair for the 2 US cars I have bought in the past. I never have them cross the border, as the fee too high for something I can easily do. The broker takes a fee for arranging things. You have to find a major city that has a high volume of cars in/out.
Dr. Dan suggested Port Huron, I tried that city last March but I couldn't get a decent bid, as it is a low volume area. I was going to get a bid from Detroit (suspect a good spot for volume?), but decided at the last minute to drive my car the whole way from Ohio & skip the transport. After buying my 250SL, 1st time driving it & it did the 5 hour drive like a champ. After it took $5,000 to safety it, so glad my car performed. But as we know that amount is a LOF in our cars... ha ha