***UPDATE***
First of all a thanks to Andy Monty who put me onto the moneysavingexpert site and their consumer revenge pages.
Expresscarprices or Express Payment Limited sent me an invoice for a car valuation I didn't want and certainly wasn't going to pay £39 for. I sent them a letter saying it was nothing to do with me and they sent a letter back saying how seriously they take fraudulent transaction and how they would pass it on to some fraud department.
Then a few days later they send me a 'reminder' giving me 7 days to pay up or they will start adding late payment fees. I talked to Consumer direct again, not particularly help the second time, and sent them another letter telling them they're not allowed to add late payment fees when the transaction is in dispute.
I found out that this company is owned by some Swedish guy and has company secretary who lives in Watford. The name on any letters or e-mails is John, no surname just John. The company charges VAT on invoices but does not display a VAT registration number. The name to look out for is Express Payment Ltd, they are the ones demanding to be paid.
I'm a little p****d off at this point, having a bad day anyway so I send them a letter telling them if they don't produce evidence of this transaction within 14 days I'll consider the matter closed. After I thought about it for a few days I decided this was not a good plan. For all I know they could add late payment fees without telling me, go to the county court and get a judgement and next thing you know I would have debt collectors on my doorstep.
So I do half an hours research into consumer protection legislation, find the Consumer Protection (Distance Selling) Regulations (2000) and bingo! I've got them! If I did order this thing they would have to, by law, have sent me a confirmation with all kinds of details including cancellation rights in it. If I had got anything like that trying to charge me £39 it would have been cancelled quick smart. You're entitled to a 7 day cooling off period when you buy stuff over the net, this can be extended to 3 months and 7 days in they don't send you all the required information in the confirmation. So even though I didn't order it, I cancelled it.
I sent a letter explaining the law to them and basically but politely telling them to shove it where the sun don't shine. It's been nearly a week and I haven't heard from them, I gave them 14 days to respond. The next step in my evil plan is to start charging them an admin fee for every letter I send them until they confirm the invoice has been cancelled
I think £10 per letter is fair.
IMPORTANT: If you get a valuation and invoice from these people don't just ignore it. I know Expresscarprices / Express Payment Ltd have got debt collectors onto other people they have demanded money from.