Auto Insurance Claims: Comprehensive claim, salvage yard, factory stereo

Question
My car recently had the factory stereo stolen from it.  When I went to the dealership for an estimate they said it would be $1700.  The car was not worth more than $10000 so I asked about trading it in.  Long story short, I purchased a new (used) car and had planned on using the insurance claim to pay towards the down payment on the new car.  
The insurance company sent an adjustor out and they issued a check for $1300 and took the deductible out of it.  How are they able to change the amount that I was quoted?  Now I'm stuck with the $1700 downpayment fee on my credit card.  Now I realize I should have had the car fixed before trading it in but they said it would take a few days to get the part in which meant that my air conditioner wouldn't work and my windows wouldn't go down because the wiring was damaged.  It was extrememly hot out and I am in sales and am required to drive a lot.  Do you have any suggestions?  Thanks

Answer
Hi Brian,

Insurance companies will almost never pay a quoted repair amount. They generally will negotiate the cost with the shop or the will shop around to see if another shop will do it for less. They may have even located a used stereo at a salvage yard for a lower price.  If you want to verify what I'm telling you, you should call the claims adjuster and ask them how the came up with their pricing when you were quoted $1700.00.  No matter what the cost ends up being they will then subtract your deductible. There's no way around that.

I hope this helps
Richard Hixenbaugh