The Airworthiness For Export is normally done by the seller in Canada. They certify it is, in fact Airworthy and that process also de-registeres the ship in Canada (C) number goes away..........Armed with this certificate and with your new N number proudly on display, you call for a US Airworthy Inspection where you will be issued a new US AW cert..........The inspection will probably be done by a DAR who charges for his inspection...... l paid $600 for the last one I had done. You also need to get the bird registered in the US by submitting bill of sale and AW for export cert to Oak City.
Hope this helps,
JJ Request your new N number, right away, this process alone can take a month or more!