Thanks for the reply. Haha, no he's based in Bath!
I do mainly a couple of short trips around the city centre each day and then perhaps a longer trip out of the city every 3 or 4 weeks. I was considering a Citreon Dispatch but Doblos are cheaper and and I'm told that the DPF is less likely to block.
I see from an article published by Warrantywise that Fiat Doblos make the top ten list in terms of reliability, though they're not in the top ten list for vans that are the cheapest to repair - it doesn't quote an average repair cost for Fiat.