Selling privately to a US buyer - help with the check list for easy transaction?

I’m selling a rather unique niche market vehicle (2012 Volvo C30 KPAX GT edition) and the most interested potential buyer would be coming up from the states upon border opening in a few weeks.

Does anyone have a quick summary of what’s required for :

1) documents i sign/provide to buyer
2) buyer getting temp insurance to drive to US
3) documents needed at border
4) expected duties and taxes - how is GST getting paid, when and where
5) documents needed to register in state of California

I would very much appreciate some help form someone with experience in getting vehicles across the border to US buyers.

Thanks in advance!


James