The post Brexit importation rules, only changed for anything imported from Europe. There has been no rule changes for ROW imports.
TBH, it’s a bit of a minefield.
You could be stung for:
- Duty, which is variable % of declared value, depending on the customs classification of what’s being imported
- UK VAT
- Shippers administration fee (which is set by the shipper, and payable by the purchaser- usually as a ‘customs release fee’
The VAT is paid by the seller, if below a certain £ value, and can be incorporated in the selling price.
If it’s above a minimum value (cant remember the actual £ value, but you can Google) then the whole collection process of VAT and UK Duty, is passed onto the company shipping the product to the UK - which is where the Shippers Admin fee also kicks in.
Having said all that, there is also a reasonable chance that you won’t get changed anything, as Customs are short staffed and overworked, like a lot of Gov departments. I’ve had a few things come in (from outside of Europe) that have been delivered with no additional costs invoiced.
On the other hand, if your seller deliberately undervalues the value of any contents, you could loose the lot, and be fined as well.
You takes your chance etc….