Wow...nuff said. anyway a good way to avoid not being screwed is not to sign the release form until the end of the shoot. That way if you don't get paid there is no way they can LEGALLY use the footage. Not a bad Idea if your working for an unknown company. But usually not necessary if you know the people well. Always agree on price before as well. Personally Iv'e been lucky but I do know people who have been burned!