E60 winscreen washer system is blocked

Recently my E60 525's windscreen washer system had become blocked and although the headlight system still works nothing apart from the occassional dribble comes out onto the screen. First off I did a little investigation work but have discovered the the problem lies at the reservoir filter end. As you cannot gain any access to the reservoir from under the bonnet I decided to speak to my local main dealer who was more than happy to charge me £144 (an hours labour) to clean out the filter. I asked what was the procedure for getting at the reservoir and was told that the wheel has to come off and then to remove the wheel arch liner to gain access, this presented me with a problem as my car has run flats therefore I have no jack to lift the car and am reluctant to put my trolley jack underneath. After I picking myself up off the floor the service guy offered to do it for £99. I kindly declined his offer and have booked the car in to have the work done by a local independant.