Julian Knight: Beware of the penalties. It's the revenge of the credit cards

It can be dangerous to get what you wish for. Exactly two years ago the Office of Fair Trading (OFT) struck a blow for consumers when it told credit card firms that they had to cap fees imposed on people who missed their repayments to £12.

The idea was that the firms would be able to recoup only the costs incurred in chasing the customer, rather than profiteering. Almost overnight, charges fell by an average of £10. But eating into the banks' bottom lines is playing with fire, and in the past two years lenders have found other ways of stinging credit card borrowers.

Withdraw money from a cash machine and you'll be lucky if you only get charged a couple of quid. Transfer your balance to another provider and a higher fee will be imposed. Miss a repayment and any 0 per cent interest rate offer will immediately vanish. Interest rates have also gone up, and some card providers have even decided to show the door to customers who pay off their balances each month or do not use their card enough to generate a big enough profit. The situation has only got worse as the credit crunch has played out.

The original OFT decision to cap fees was the right one. Morally, charges of up to £25 a time couldn't be justified. But many people who never miss a repayment are now being hit in the pocket. Fortunately, some firms – such as the AA, Barclaycard (Simplicity Visa) and Britannia – have so far steered clear of piling on the fees and upping rates.

The advice is to check what stealth charges your provider might have been loading on to your card over the past two years, and then vote with your feet.

Haunted housing

I had really hoped I would have been able to stop writing about the credit crunch by now. But instead it's dominating our finances more and more. And last week it probably dawned on homeowners that they could get a lot poorer. A dramatic fall in the number of mortgages available – from 16,000 last July to around 5,000 today – and much tighter lending criteria are choking the life out of the housing market.

Property website Prime- move.com revealed last Thursday that only around one in five homes up for sale last August have actually changed hands; the rest have been withdrawn from sale or are clogging up estate agents' files.

As we reveal on page 18, fewer buyers makes price falls inevitable. It also means more people renting and, as we show on page 20, this is having an inflationary effect on rents. This in turn could reduce the chances of would-be first-time buyers getting a big enough deposit together in order to purchase, as they have to use their extra cash to pay the rent. The property market has entered a new cycle and it could get very messy.