Exhaust

Unless its in your policy expect the damaged aftermarket parts to be a total loss. First thing you will need is to get it inspected by your insurance. From there its up to you decide for them to cut you a check and decide whether or not you want to fix it or have a cheaper shop to fix it. The insurance normally has its recommended certified body shops though. Just by browsing the private classifieds, you could pretty much make your car like new for very, very cheap granted you do most of the install or know a shop at a good hourly rate. No clue how bad the car is, and that engine sounds like it could be in bad shape. Did air bags deploy? Got any pics? Also was a police report filed?

Edit: Air bags deployed, sounds totaled.