Just a bit of information others might find useful.
We have just been to pay our Trafik Sigorta at the Baris office above BIM in Calis. In previous years we had paid with our Nationwide credit card, however they have now changed the rules and can only accept payments by cash or a Turkish Bank CREDIT card -
not a debit/cash card and not a foreign bank credit card.
So if you don't have a Turkish credit card make sure you take cash to cover your payment.
Good job I didn't go shopping first !!