It's been a terrific summer in terms of sales throughout the auto industry. Except for sales of the classic summer car.

Convertible sales typically claim about 2 percent of the overall auto market, as they did in 2011. But in 2012, a year in which overall U.S. sales are expected to climb into the neighborhood of 14 or 15 million units, up 22 percent from a year ago, droptop sales have slackened to approximately 1 percent of the market.

Part of the problem: While older Americans have fond memories of convertibles that stood as symbols of their adolescence, younger drivers don't feel the same way. Smart Money reports that drivers 35 years old or younger accounted for less than 5 percent of convertible sales last year.

Another part of the problem: Cost. Convertibles cost about $5,000 more, on average, than comparable coupes. Given the limits of the economy in recent years, it's reasonable to assume droptops are a bit over the top – an indulgence that more frugal consumers may appreciate, but ultimately decline to purchase.

In that spirit, we've gone searching for the most affordable convertibles out there that remain high in quality. Here's a look at the best convertibles that cost less than $25,000 – perhaps a bargain, if you're trying to survive this summer's heatwave.