I have served in some capacity on the WJM-USA team for the past 10 years. Other than an occasional receiver and minimal assistance from some vendors, the costs are all taken care of by the pilots. It can be very expensive. I know the trip to the Hungary and North Ireland costs well over $15K when you figure in the cost of a competitive plane, 10-12 days of hotel accomodations, food, travel to the site, rental cars, registration fees, and one of the biggest costs - shipping of the crate.
Now the question is does the "guys work together"? and to that I say an affirmative yes. Sometimes these guys live many states away and don't fly togther but when they get to the WJM, they are a TEAM. I have seen guys spend all night helping a fellow team member, and sometimes a competitor, fix a model that was damaged. I have seen Scott Harris actually donate one of his planes to another team when their plane was damaged prior to the beginning of the competition. These guys are salt of the earth and it is a shame that some of the companies do not do more to help them when they go off to compete. I know in the past that Kingtech and JetCentral both provided turbines to the team members and if they used them in competition they were allowed to keep them. Some did, some did not. But Barry and Eric both stepped up to the plate as far as I am concerned and I give credit to both of them for their generosity.
I said of that to say this, if you are serious about competing in the WJM plan on spending the money. It is not cheap, but it is a fantastic experience and you will meet some amazing people. If you told me when I was a teenager that one day I would get to drink ice cold Vodka with a Russian while sitting next to a B-52 in a hangar at the USAF Museum I would have told you that you were crazy.