Following are my suggestions:
1. Get the insurance information from the transport co. driver, threaten to file police complaint if they refuse to give you the information
2. Find out when did the accident happen, exact details. If accident happened while the transport co. driver was driving the vehicle, his/her insurance co. should cover the damage. Typically transport cos. have their own insurance which overrides the drivers insurance, find out if this is true, if so get the transport cos. insurance information.
3. Contact the drivers/transport cos. insurance directly, they will probably open a claim for you, if they refuse to open claim, call your insurance co. and give them details, they will then call the other insurance co. to open a claim.
4. Get a list of BMW authorized body shops in your area from the bmwusa.com website, additionally get a list of recommendations from this forum and other X5 forums. BMW Authorized body shops might not be covered by the insurance co., I would recommend going with a body shop covered by the insurance co. because that eliminates any money going out of your pocket.
4. If the drivers/transport cos. insurance opens a claim then things are easy and simple for you, just give them the names of the body shops you would like to take the car to and if they cover any of them, they will directly setup an appointment for you.
5. The body shop will give you an estimate, if the repair costs come out to be more, then they will directly contact the insurance co. and you won't be hassled.

Good Luck

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2008 E70 X5 3.0si
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2019 G30 530e
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2018 F83 M4
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2009 E93 335i (Sold)
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E36 328is GoKart (Sold)
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