Hi Clive
I have got Gardiners systems fitted, i was there guinea pig.
The tanks are 650 litres, i wish i had gone down that route earlier, everythings running smooth no problems at all, everything is self contained behind a panel.
I was going to fit my new van out with some of my spares, i just cant bring myself to diy anymore, so the van is just used on shops, trad at the moment.
650 l usually lasts a day, i prefer one man per van these days, we find 2 people dont even earn 30% more on average than one person. it works on big jobs but when you have a lot of stop/starts forget it.