Be wary of agencies that don't accept credit cards. The first question is, "Why not?" More than likely it's a scam, since your credit card company will protect you from unscrupulous people. Tell such folks, "No card, no deal." If you are booking airfare, hotel, accommodations  etc., you're probably safe. Only use the four major credit card companies VISA, MasterCard, American Express and Discover as they guarantee your purchases from frauds and scams.