There’s an unprecedented number of diesel used cars around at the moment. Why? Because next month it will be three years since the Government changed the way it taxed company cars from business miles covered to carbon dioxide emissions produced by the car.

It prompted a large-scale switch from petrol to diesel and the trend will continue as more of business users see the financial benefit of minimising BIK taxation – and after three years these cars are flooding on to the used car market.

We have heard doom and gloom from market analysts about how the premium for a diesel used car will disappear, and how traders will find it difficult to foist three-year-old diesels on buyers who have only owned petrol cars in the past.

Punters’ views on diesel cars may have been formed through memories of noisy, smoky, poorly maintained vehicles. But if you look at TV campaigns, like the one Volkswagen ran where drivers left notes to remind themselves their car ran on diesel, the manufacturers are hammering home the message that diesel cars can be as good as or better than their petrol equivalents.

Family car buyers can now take their pick of sensible mileage Citroen C5 HDis, Renault Laguna dCis, Ford Mondeo TDCis or Puegeot 307 HDis for under £6,000. For a bit more, they could find Honda Civic CTDis and VW Golf TDIs.

And if they use Parker’s, expect your customers to know the difference between a Ford TDdi and a TDCi or a PSA TD and HDI. They will part with up to £500 more for one with the latest diesel technology over an old-tech engine.

A slightly newer petrol Mondeo may be on offer for the same money, but when it comes to spending their own cash on fuel you may be surprised by their interest diesels.