In terms of car repairs, the quotes that insurance companies obtain are almost always for official stealership repairs or their "trusted" repair centers. A third party mechanic can almost always repair it just as well for much less, but of course you may be out of the warranty if that's important to you.

If you car is already out of warranty though, instead of scrapping it and taking whatever low ball value figure they give and buying another car, it may be cheaper to pay for the repair out of pocket elsewhere.