D2's have a common fault on the aircon in that there is a pipe that goes from the front of the grill, through a clip at the side of the passenger side headlight and the pipe corrodes/wears away in the clip. Have a look there first as if its only a small leak, you might find Quickfit can recharge your aircon and you get an immediate result, but a couple of weeks later you will be back where you started. Also remember your aircon hasn't been used all winter and the seals may have dried out/perished on some pipes.
Have you checked that the aircon compressor is running and that all associated fuses are intact?
I wouldn't be getting Kwikfit to do my aircon, "jack of all trades master of none" springs to my mind. Get an a specialist aircon company to check your system, get them to evacuate all the remaining gas and see if the system holds a vaccum, before you get it recharged, if it doesnt they can put a leak detector dye in to see where its leaking. A specialist wont charge much more than quickfit and it may also save you money in that you only get the job done once.
