Do not give them cash or checks. First you'll get a knock on your door. It will be a college student asking you if you could look at something. They'll say if they get enough people to do it they'll win a scholarship in a contest. They give you a laminated paper with their picture on it and supposed information. They'll show you three more laminated papers with info on both sides. They'll have 'Codes' and magazine names. They'll ask you to pick out a magazine. You pick out one and they'll say they that for every magazine they'll get closer to winning. Then they'll say they need to come in. Whether its because they need to use the bathroom, or because its raining, cold, or hot outside. Then they'll get very comfortable in your house. sitting in your chair, talking to your kids. Then they start telling you their life story trying to get you to relate to them more. So you feel bad. They'll say its 15 for each magazine and they'll ask if you have cash. If you don't they'll say they take checks. Then they'll tell you to leave the 'pay to the order of' blank because their boss will put a company stamp there.
Then the next day they'll write their name in, cash their check and thank heaven for suckers. And if you paid cash then your screwed. If you paid with check, immediately cancel your check right now. If you researched after they left you may still have time.