The GEM site is having maintenance at the moment so best give them a call, I seem to remember it being about £80 but you can add spouse or whole family membership.
With my RAC cover, I had a tyre burst on my Harley at the MOT station. They refused to pick it up as it wasn't MOT'd even though it was at the MOT station and had been booked in. Took 2 days off arguing to get them to pick it up.
I had a car break down on the way to an MOT with GEM and when I reported the breakdown I told them it had no MOT as it was going in for the MOT. Simple reply..........."No problem"