Certain traders can be made liable for the unpaid VAT of another VAT-registered business when you buy or sell specified goods. HMRC have recently updated VAT notice 726 which advises traders to carry out due diligence into their supply chain.
The specified goods are any equipment made or adapted for use as a telephone and any other equipment made or adapted for use in connection with telephones or telecommunication, such as SIM cards.
Also included is equipment made or adapted for use as a computer and any other equipment for use in connection with computers or computer systems and also other electronic equipment for use by individuals for the purposes of leisure, amusement or entertainment, such as Satnavs and games consoles.