>> The hand brake was stated to have been adjusted, it now remains on after releasing and breaks free with a noticeable thud and jerk.

Perhaps you got used to the handbrake operating the way it did and now it operates as it should?

The hand brake had neen exceptionlally good over the seven years we have owned the car. However, in recent times it had become less and less effective on an incline and had to be pulled on harder. This to me hinted that an adjustment would be needed to restore the otherwise good performance. What was done did not achieve an improvement but also left the operation very doubtfull. In my experience I would examine the mechanism to check for free movement of the parts and also the state of the brake lining. Which is why I am seeking the manual before diving in myself. If all else fails then I suppose I will have to fall back on my own engineering skills and experience or even sell the car. But thanks anyway for at least thinking about it.

The hand brake had neen exceptionlally good over the seven years we have owned the car. However, in recent times it had become less and less effective on an incline and had to be pulled on harder. This to me hinted that an adjustment would be needed to restore the otherwise good performance.

Brakes should need very little or no adjustment - the brake calipers should self adjust as the pads wear - If in recent times it has become less effective then it suggests that the brakes need attention eg new pads / disks or seized calipers (pistons or whole caliper can't move)

Strip down the rear brakes to check and sort. If you are not sure what to do then find an independant garage who does - brakes are life critical!

Couple of "should" s above save it from being a work of fiction.

Automatic adjusters on older cars frequently don't work. I don't think they've ever worked on any car I've ever bought.

When they don't work manual adjustment is required, which is much more difficult with an automatic adjuster than with a manual one.

(Manual brake adjusters are my idea of automotive luxury, last experienced on a Lada Mk1 saloon many years ago. Can't afford it now.)

You will probably have to do the mechanical equivalent of keyhole surgery through the drum (I'm assuming this car isn't discs on the back) backplate in order to back off the shoes enough to get the drums off. If there's a wear lip you might have to hit them a lot too.

Once you get the drums off and clean everything off and lubricate it (and maybe grind off the wear lip) the automatic adjusters might start to work, but I wouldn't bet on it. If they dont you'll just have to repeat the manual procedure every now and then. It should get easier.

This is all finicky and a bit of a pain, which tends to mean that you can't trust anyone else to do it properly for you.

Ineffective hadbrakes tend to be due to crud gumming up the pad mouting points and all the surfaces at the disk where pads move. Requires a full stripdown , clean , bgrease with silicon grease and carefull reassembly. Unsurprising due to frequent bombardment by salty water mixed with grit and mud.

Jazz's rear handbrake became slowly less efficient in 5 years of ownership (full Honda service0, so I stripped it down, new pads etc and serviced as above.

Now very efficient.

Time consuming job and messy tho.. 1 hour each side..(I fitted all new fitting metal)..