I've moved from UK to Malaysia, Malaysia to Australia and Australia to NZ (much the same stuff each time, obviously) and filled a 20 foot container each time - usually cost in the region of 5000 usd. I found quotes varied quite alot but so did the quality of the packers - it was a LOT less hassle having them pack everything up and got better insurance if they did it too. And every time they refused to quote unless they viewed the stuff - I guess they know folks are not as good at them as estimating size.