For UK legislation there is no difference between retail & second hand RIF sales
If it was a sale within the UK then even a private seller is the one liable for a compliant VCRA RIF sale - the buyer should demonstrate a VCRA defence to justify the RIF sale, but it is the seller who is legally liable
But Jersey is not part of the UK, therefore it would be an import and the importer (buyer) is responsible for justifying a RIF import
This could be difficult and complicated