THE British love affair with convertibles looks set to continue, despite the wet May weather.

Vehicle auction company BCA is reporting rising prices for soft tops, in the run-up to the main summer months.

BCA's network operations director, Simon Henstock, said: "Values for convertibles are more seasonal than other models, with prices rising in line with the temperature.

"Average prices for a typical three-year old, 30,000-mile convertible sold at BCA increased by £339 (2.4 per cent) to £13,718 in the first three months of this year, making this a good time for anyone selling a soft top."

Despite notoriously changeable weather, British motorists buy more convertibles than any of their Continental cousins.

The residual values of used convertibles increased, month-on-month, by up to five per cent during May, as demand improved in response to prolonged spells of dry and sunny weather.

Reporting on the seasonal uplift in values, EurotaxGlass's has found that a number of volume-brand drop-tops retain a far greater proportion of their value than prestige-brand models from the likes of BMW, Lexus and Maserati.

While the Ferrari F430 Spider holds on to its value better than any other 12-month-old convertible on sale in the UK (a typical 06-plate example retaining 97 per cent of its original list price as a trade value), hot on its heels is the rather more humble Volkswagen Eos (at 94 per cent retained value in 2.0 TDI Sport guise).

"This analysis offers some stark examples of how changing patterns of supply and demand are challenging the market's preconceptions of which cars hold their value best," said Jeff Paterson, senior car editor at EurotaxGlass's.

"Few would expect convertibles such as the Vauxhall Astra Twin Top and Mitsubishi Colt Cabriolet to boast residual values stronger than those of a BMW Z4."

Below the Volkswagen Eos, in joint third spot, were the Porsche Boxster S and Mercedes-Benz SLK55 AMG (87 per cent). Close behind in fifth place is the MINI Cooper S Convertible (85 per cent), whose mighty residual value performance is identical to that of two high-performance prestige models, the Audi RS4 Cabriolet, and the Jaguar XK Convertible.

Rounding off the Top 10 are the Porsche 911 3.8 Carrera S Convertible (84 per cent), the Aston Martin DB9 Volante Convertible (82 per cent), and the Mazda MX-5 1.8 Convertible and BMW 330d Convertible (both at 78 per cent).

EurotaxGlass's says the convertible market continues to be affected by seasonal peaks and troughs - values fall at a more pronounced rate than the rest of the used car market in autumn and winter, then rise in spring when conventional cars continue to fall in value.

There are signs that some buyers are not embracing the coupé-convertible (folding hard-top) format for aesthetic reasons.

Dealers representing a variety of marques have reported that some prospective buyers have rejected coupé-convertibles on the basis that it is less obvious to the outside world that they are driving a convertible when the roof is up.

"It seems discreet coupé-convertible styling does not flatter the vanity of some owners," says Paterson.

Furthermore, while practicality is not high up on the agenda of used car buyers, a folding metal roof does compromise boot space more severely than a fabric roof.

Richard Crosthwaite, prestige car editor at EurotaxGlass's, adds: "This is a fashion-led market, where the values of prestige-brand models in particular are influenced by changing tastes and the arrival of new models. Ownership periods are typically shorter than for conventional road cars, with buyers more likely to swap into what they perceive to be the next big thing'."