US Import duties on resale of personal import.

[Alan-4rcva]

Hi all, not sure if anyone knows the answer to this, but if I’ve brought in a personal import that I owned in the US previously, so didn’t have to pay Import duty and VAT, how long do I have to own it before I can sell it without being liable for the charges by HMRC, or if I buy a vehicle from someone else who personally imported a vehicle they previously owned in the US, will I be liable for tax and duty if they sell it too soon ? Thanks in advance!