'THE BMW 3-series never goes out of fashion. The story began in 1966, with the 1602 and 2002, which sold almost 862,000 worldwide. This was followed by the E21 3-series, produced between 1975 and 1983, selling 1,364,038 worldwide, of which BMW Great Britain sold 6,463 in 1980 alone.

If those figures looked impressive back then, it is nothing compared to today's sales performance. UK sales have risen by more than 900% in 20 years to a total of 62,644 in 2002 and this year looks set to beat even that record.

Of course, that kind of success brings with it the risk of oversupply depressing residual values. But the car retains an appeal that has been so powerful that values remain the subject of endless admiration.

BMW has handled 3-series brilliantly, with a model mix that enables rises in volume without boring the public. For example, saloons accounted for 40.6% of sales in 2002, coupes 19.4%, Compacts 14.8%, Touring and convertibles 11.4% and the Z3 2.4%. This means the range offers something for everybody – except a cheap and cheerful model.

The vast majority, about 75%, are business sales and the average age of the new 3-series buyer is 45 years-old, with 78% of them male. However, when they reach the used market there is a very different profile of buyer, changing as the car on offer gets older. For example, an older Beemer is a younger person's car and you will find more women at the wheel. But although BMW has managed to create a car that is desirable whatever its age, the dealer network is not particularly happy selling cars which are more than three years old.

The upshot of this is that the three-quarters of business cars which return after three years are not then sold within the network, but more likely by specialist dealers who can handle as many nice examples as they can get hold of.

Taking 2002's figures of 62,644 sales, of which 75% are business sales, then 2005 may bring in the region of 48,000 used three-year-old models into the market, which are likely to be sold by non-BMW dealers.

This is not seen as a problem by either the BMW dealer or the trade. Everyone is getting a taste of the action and some of the profit. It is beneficial to all to specialise in what you know and understand. In this case, up to three years old within the franchise and over three years by independent dealers.

Whenever the next generation 3-series arrives, it will no doubt be a similar success, providing it looks good and does not change too radically. 3-series buyers know what they want and image is almost everything.

Dealers still confirm the 318i as the backbone of the range, but when it comes to the Coupe or Cabriolet then it has to be a six-cylinder engine.

Since the arrival of the 320d in 1999 a whole new market – and new type of customer – has been walking into BMW dealerships.

Such a dynamic and enduring marque is remarkable. Fleets are lucky to have the 3-series as a car which consistently keeps the user and the disposal manager happy.'