Ended up going for:
1x Gtechniq I2 Tri-Clean 500ml Antibacterial All Surface Interior Cleaner, for the interior and plastics
1x Autobrite Alcantara and SuedeSurface Cleaner 500ml, for the steering wheel and buckets
2x Autobrite Very Cherry Non Acid Wheel Cleaner 500ml, at dilution ratios of 10:1 I calculate that I will have gone through both o of those with just 10L of water which is what? 3 washes? Seems too little. How much water should I be using?
and a couple of Gtechniq MF1 microfibers.
Most money I've ever spent on cleaning products
(I know how ridiculous that will sound to detailing guys!)