Old shape vauxhall combo crew van. Make sure it is a 2000, not the 1700 (thats gvw) version though, it has a 700kg (or thereabouts) payload. Problem with the berlingo/partner cars, is that they are all going to be the equivalent of the 600kg payload version of the van. And while there are plenty on here who wouldnt bat an eyelid regarding putting a 2-300l tank right in the back of one, it would almost certainly be exceeding the rear axle weight limit (if you were using the van, the tank would be between the axles so would be fine). You may well find an 800kg version of the berlingo/partner that has been converted to a crew van, but then you will have to decide whether the conversion has been done properly. Other possibility would be the transit connect, which, like the combo, comes as a factory crew van. Again though, go for a higher payload version, the 210 or 220 swb, or the 230 lwb.