HANOVER, Germany - Independent German contract carmaker and convertible roof-top specialist Karmann is nearing liquidation as new orders remain out of sight and customers remain unwilling to pay their bills.

If new money does not arrive quickly, liquidity will tend towards zero soon, a spokesman for administrator Ottmar Hermann said on Friday. Without money we will not be able to pursue business and will not be able to avoid closure.

Customers owe Karmann an amount in the double-digit million euro range, sources told Reuters.

The administrator, and client Volkswagen declined to comment. A Daimler spokesman said discussions with Karman about unpaid bills were ongoing.

Most famous for the 1950s VW Beetle-based coupe dubbed the Karmann Ghia, the company also developed the retractable hardtop roof first introduced with the Mercedes-Benz SLK before the idea was later copied by competitors, finding widespread use in popular volume models like the Peugeot 207cc.

In recent years, a trend among auto makers to reduce outsourcing the assembly of entire models weighed on Karmann's order book. After delivering its last Mercedes CLK in June, Karmann was left without work.

Hopes that investors might at least be willing to buy parts of the business have dwindled in the meantime. Interest is gone, a source close to the matter told Reuters.

According to sources, auto suppliers Magna CTS and CIE Automotive had considered a bid.

But while Magna is tied up with buying a stake in car maker Opel, Spain's CIE is struggling with a debt pile of 650 million euros and a sharp drop in operative earnings in the first six months of 2009.

Both companies declined to comment.

After drastic job cuts in the last months, there are 1,700 jobs remaining. (Reporting by Arno Schuetze in Hanover and Tomas Gonzalez in Madrid)