You really don't need to make an offer at all as long as you are prepared to accept the phone calls and letters for the next 6 years . Yes, your credit file will be blemished but if you seriously can't afford to pay them or you don't want to pay them then there is very little they can do about it . Yes they can sell the debt to a third party , yes they can write or call you about the debt but they cannot take you to court to obtain a judgement and as long as you don't acknowledge that you owe the debt then after 6 years it becomes statute barred . If they do sell the debt just send a copy of the letter stating that Nat West are unable to provide a copy of the original agreement and then they will back off !

An interesting point I noted when looking at issues in respect of Goldfish was that the account statements were issued by Goldfish Card Services Ltd ( co reg 03722587) and the Terms and Conditions were supplied by Goldfish Bank Ltd (co reg 06125763) . So I would suggest that you check on exactly what appears and from whom because the "unenforceability" path could be quite favourable . Furthermore both companies have different registered offices and both are in liquidation .

Just as a matter of interest were you aware that Goldfish Card Services Ltd previously known as Morgan Stanley Dean Witter etc had been placed into liquidation . Incidentally what is the position in respect of the creditor supplying a letter of assignment when the debt is transferred from one card company to another ? This may provide an additional route . I found this out when I tried to trace if a Morgan Stanley Bank International Ltd credit card to see if it then became either a credit card of Goldfish Bank Ltd or Goldfish Card Services Ltd and found by chance both companies are now in liquidation ! A S77-8 and DSAR request to the liquidators might prove interesting .