Gulp!
Are we going to need to disconnect it? Do I need to find a friendly electrician to help me collect it? When we go to see it, should I ask to see it start up?
Absolutely on all counts, this unit is a gift at £500 for the engine and alternator alone, however if the control panel isn't working you could end up with an extremely large bill to fix it. Having said that, with the correct 'generator start module' or 'off grid inverter' it may not be required. The other serious consideration is that these sets are EXTREMELY heavy.
http://lifeattheendoftheroad.wordpress.com/2013/09/12/up-to-harrys-shed/http://lifeattheendoftheroad.wordpress.com/2013/09/01/awaiting-midnight/ Short scaffolding tubes, planks, levers and a winch if you can't find a forklift truck

I'm pretty sure that I have the email address of a man in Devon who's a Lister expert, if I can find it I'll PM it to you.
Good luck, Paul