If you mean customs as it crosses the border into the UK, if it counts as a
collectable (mostly it's not a gold investment coin) then the margin scheme
can apply and a reduced rate of VAT at 5% can apply. I have no idea how you
would do this privately, I'd guess HMCR would try and hit for 17.5% if you
bought from an overseas website, so importing via a VAT registered entity
then buying it off that entity might be worthwhile.
The VAT guide (Section 718) on this is clear as mud as to what happens if
you bring a coin in privately and then find it's valuable once in the UK.
On the other hand if you are buying from a dealer in coins and they bought
the coin from a private indvidual in the UK and they are using the margin
scheme then the VAT is normally only charged on their profit i.e.
Buying price: £700
Selling price £1000
VAT is (1000-700) * 17.5 / 117.5 = £44.68 and the goods were £1000-44.68 so
As far as I can see legal tender doesn't matter. i.e. if it's a coin with an
error so counts as a collectible it could still be legal tender in the