First off, whenever you are in a car accident and there is damage to your vehicle and you are injured, you have two separate claims. The first is the damage to your vehicle. This is called the property damage claim. Many people handle this entirely on their own, without a lawyer.
The key is that you do not sign any release without reading and understanding it. Once you sign a release that is the end of the claim. A property damage release should say “Property Damage Release” on it. If it says “General Release” then you are settling everything including your personal injury claim. Make sure you know what you are signing. I once had someone call me to tell me that they had signed for an advance on their settlement –when they had in fact signed a general release settling their case. This mistake cost them thousands of dollars and made it so I couldn’t help them.
The check when it is paid to you should say "Property Damage" on it or something similar to that. I also advise clients that if at all possible to have the insurance company pay the body shop directly. That way the funds never go into your hands and go directly to the body shop. The benefit to this is that if there is a problem and the damage is more severe than the adjuster originally thought, the body shop will take it up directly with the insurance company and you will not have to be involved in any negotiation. The property damage claim covers several things and covers the cost to repair your vehicle or the market value of your vehicle whichever is larger. This means that if the insurance company can repair your vehicle cheaper than what it is worth they will do so. You have the right to take your car to any body shop you want. If the estimate given to you by the insurance company is different than the estimate the body shop has I encourage you to have the body shop call your insurance company directly, that way they can negotiate with the insurance company and you don't have to. I would caution you against taking it to a shop and telling them to work on the vehicle prior to the adjuster saying it. This is an easy way to cause great difficulty and make it harder for us to close your property damage claim. An insurance adjuster is likely to claim that some of your damage is pre-existing or prior to this incident, therefore they do not want to pay for the coverage. I would always encourage you to have the adjuster from the insurance company come and look at your vehicle prior to any work being done on it. Sometimes clients ask me about aftermarket or second hand parts and whether an insurance company is able to use older parts in the vehicle. Unfortunately, the law does allow them to do this. The rationale behind the law is that the parts are not new in your car therefore you are not entitled to new parts in your car again.