I had a similar problem with mine. 1st time it happened was at IVA. Drove there, drove in, turned off. They did all the other tests and then it would not start even with their big bumper battery. IVA fail! Pushed it out, called AA. Whilst waiting i thought one more try and all OK.

Was fine a long time and then occasionally happened so I have a 6" piece of wire with a female spade connector on the end. If it wont start, I turn the ignition on, slip the starter solenoid cable off the solenoid, slip the spade on and then touch the bare other end to the battery connection on the starter motor and away we go!.

After about 12 months I did change the ignition switch as something was clearly wrong in there. The contacts had gone and were not closing to the starter solenoid. That was £75 from Wayne Ellet.