Compensation for Vehicle

I have to date attended a  national garage outlet on 3 separate occasions during the past 3 months, complaining of the same company commercial vehicle fault, i.e. front brakes sticking and wearing excessively, causing loss of power and speed and increased fuel consumption. To date we have lost over 6 hours work time waiting in the centre (the last time being over 3 hours) and have incurred billing costs totalling I believe over Â?400. Over the past 3 months since my first visit we have incurred a massive and continued increase in fuel consumption costs and loss of both journey and work time. My individual daily earnings over this period are in the region of Â?360 per day, charged out at my standard hourly rate of Â?45.00 per hour.
Following my latest attendance on 10th December 2011 for remedy of the same and original fault, where both the front brake discs (3rd set), pads (3rd set) and callipers (3 in total) and a connective hose were changed, things looked to be initially remedied on the return journey home.
However, imagine my absolute horror when the following day, having collected my 4 yr old son locally for the day in the vehicle and travelling along the motorway at approximately 60mph, the brakes began to violently judder and veer violently to the right. My son was visibly shaken and scared. I immediately fought to steer the vehicle onto the hard shoulder and put on my hazard lights and very slowly made my way to the nearest exit, which was within sight. My intention was to leave the busy motorway, given the fading light and poor weather conditions (it was raining heavily) and move to a safer place in which to stop with my son. Having reached the entrance to a nearby car park, the brakes then seized completely, causing a traffic obstruction and the vehicle would not move and there was a thick acrid smell and smoke emitting from both front wheels entering the cab. I immediately removed my son from the vehicle to the roadside, through fear for his safety and due
to him suffering a coughing fit and struggling to breathe properly. On inspecting the front wheels I could see that both front discs were glowing red hot and smoking. I believe that if it were not for the rain and wet conditions the vehicle would have ignited.
As a result of this, I had no choice but to contact a recovery service, and as I was not a member, had to join at the roadside at a cost of Â?127.00, in order to ensure the vehicle was professionally inspected and subsequently recovered to my home and to ensure my son was removed from the poor weather conditions and to safety. We waited some 40minutes in the pouring rain as it was unsafe to re-enter the vehicle.
We are in possession of a corroborative report from the Recovery operative.
As a result of this incident, my day with my son (I see him twice a month) was also completely ruined.
Also, as a result of this incident I have now had to reschedule my workload for Monday 12th December 2011 onto Saturday 17th December 2011, however, should I now be left without a means of transport for my work duties, I will incur loss of work through cancelled confirmed bookings currently totalling Â?1102.00.
Furthermore, I have now incurred further costs in relation to vehicle hire of Â?140.00 and loss of business of Â?257.00.
Losses:
Â?400.00 unnecessary repair bills from yourselves.
Â?140.00 vehicle hire.
Â?140.00 loss of work.
Â?480.00 Loss of bookable schedule time of 16 hours at Â?30.00 per hour.
(Sat & Sun filled with Mon & Tues work).
Â?127.00 AA Membership not wanted.
1 day with son completely ruined.

My question is this. The Area Manager wishes to meet over coffee to discuss the way forward. What figure should I be looking for?