Mercedes-Benz EQS owners must pay $800 a year for rear-steer

German owners of the recently-launched 2021 Mercedes-Benz EQS will be offered the chance to pay for some of the electric luxury car's options on a yearly subscription basis – including its enhanced rear-wheel steering system.

According Auto Motor Und Sport, the pilot scheme will initially be limited to Germany, but the subscription service is expected to be rolled out to other markets if it proves successful.

Offering options on a subscription or pay-to-use basis is the latest trend by car-makers to generate new revenue streams.

In the case of the pure-electric Mercedes-Benz EQS, the German report suggests owners will be charged €489 ($A780) a year for extras like the enhanced rear-steer option.

As standard, all EQS models come with an agility-boosting rear-wheel steering axle, but with the enhanced set-up the back wheels can pivot up to 10 degrees – more than twice as far as the standard 4.5-degree set-up.

This makes a dramatic difference to the big saloon's nimbleness in the city, slashing its turning circle to just 10.9m – 2.0m less than standard.

Better still, turning the wheels in the opposite direction at speeds of less than 60km/h makes parking in urban areas a cinch, especially with the semi-autonomous Active Parking Assist tech.

Above 60km/h the system turns the rears in the same way as the fronts, providing more precise and reactive handling.

Cleverly, both the standard and enhanced rear-steer system use the same hardware, so it's the extra software owners will pay for.

And they won't even have to visit their dealership to apply the changes, with Mercedes-Benz able to provide the update over the air.

In Germany, if you subscribe to have the enhanced rear steering for three years, Mercedes-Benz will lower the cost to €1169 ($A1900) over the period.

The more sophisticated steering system can only be ordered if you already have the more advanced parking packaged fitted that gets a 360-degree camera.

Volkswagen is reportedly considering offering its next-gen hands-free autonomous cruise control on a pay-per-use basis that could see customers hand over as much as €7 ($A11) per hour.

Last year, Tesla was the subject of investigations by US consumer organisations after owners reported options like Ludicrous Mode and Enhanced Autopilot had been removed post-sale because the second owner hadn’t paid for them.