Opinions please!!!!

Shelby

So this person contacted me on Sitter City, a baby sitting website. He wants to pay me $375 a week to baby sit his kids. But he is moving here from California and wants to mail me my first check before a week before their arrival. He wants my address so his company can send me the check but I'm so nervous to someone I've never met my address! Sitter City is a reputable place but anyone can jump on there. Opinions?? Am I being too cautious?