Noice. I've been pleasantly surprised by the cheapy Aukey thing I got, picture quality is plenty good at night, and if I set it to record on motion, I can just leave it plugged into the cigarette socket 24/7 and it never drains the battery (not a shock given it's probably drawing 300-500MaH at worst)
Anyway, got some brake cleaner and gave the various rubber lines a bit of a skoosh tonight when I came back in. Engine was hot so didn't want to douse it in highly flammable solvent

but nothing obvious happened - idled smooth.
I'll probably give it a slightly more aggressive dose tomorrow after work in the works car park, but the only piece of vacuum pipe I can see that's a bit shonky is the bit at the exhaust flap solenoid - although crimping it closed didn't seem to make any difference to idle.
I'll cut it short and reseat it on the exhaust solenoid (so it's at least properly sealed and not pulling air in) and see if that makes any difference.
Halfords have their five piece car lifting kit (2 chocks, 2 axle stands, one 2-ton jack, one wheeled thingy to scoot under the car) for £50 - given my brother seems to be feckless at remembering to bring a jack over - or buy a new one

- I think I'll check the minimum heights of that jack, the car, and see if that'll work - I need to adjust the handbrake, so I need to get the car up and I'm fucked if I'm trusting the scissor jack in the boot.