Thanks Guys for all the helpful advice. The problem is that although we have electricity in our communal garage (and in our downstairs store) the electricity is not charged to individual apartments, but is paid centrally and thus is part of the service charge.
One of the other apartment owners put his Lambo on a battery conditioner plugged into a common point and this provoked a row with one of the other owners over whether he was entitled to do this. We then got a circular from the management company entitled "Electricity Theft"! I think these conditioners cost pence per hour to run, but that's the problem with communal living.
Head Office has now been elected to the Management Committee with the sole aim of getting a solution to this problem (at last that's my take!) and I'll let you know how we progress.
In the meantime, we are back later in the month and I know the AeroMax's battery will be completely flat.
