Either the handbrake mechanism is partly seized or the return spring on the parking brake pedal mechanism is broken.

The sales bod managed to get it to release by putting it in reverse, that means its probably sticking inside the drums (i suspect severe rust on the drum), the parking brake is the top hat design, where standard rear disc brakes are used, and seperate small drum brake provides the parking brake.

Depending how good previous maintenance has been, these drums get very badly corroded inside as the shoes never normally get applied during driving to clean the surface up.

Assuming you've got the brake off now, you could drive somewhere quiet and gently apply the parking brake as you drive along, it might take a few minutes to clean the surface, and it might be too badly corroded anyway.

Its a fairly easy DIY, but maybe for the more advanced DIYer, new rear disc/drums, new pads, new shoes, competent indy, about 2 hours and £80ish in parts.

I say 2 hours because the rear shoes if they need replacing are awkward.

Edited by gordonbennet on 30/03/2014 at 19:10