Thats just the cost of the display, building it, paying carpenters, wood etc. Then factoring in each persons travel to get their and renting a truck to get the stuff there. Its expensive. Next year we plan on bringing some veterans over from the States so we will put them etc. It's worth it though, you can see our display here.
http://www.modernforces.com/2012_WP_camp.htm
And yes we have to pay for the MV entry.