I went to the usual petrol station for 13kg of propane @£38 (which I knew was expensive, but I go there cause everywhere else is usually closed-just happened to be middle of the day I went) they had ran out but sent me to the caravan shop a mile away who had loads and was only £27!
I'm on calor at that price, I've heard that 'flogas' are a tenner cheaper-don't know if that makes them £28 or £17 though.
Didn't realise the price difference till yesterday!