Which jack!

Hi all. Every weekend I seem to find another item that would make life easier and safer for the caravan experience. Last week (after reading another caravan magazine) it was made quite clear that a "tauque wrench" would be a wise purchase. Now, I have only been caravanning for a short while but now I am aware that a jack would/should be purchased. After lookiing on websites I am amazed at the price of some of these jacks. I have a 2011 Coachman Amara 570/6 with an mtlb of 1600kg and an Al-ko chassis. I can't believe that a "light weight" side jack for this is £120! Can anyone advise of a good, light, no hassle jack that just does what it's meant to without having to bolt things on.