Sales scams are as old as humanity, but the Internet has introduced a whole new way to rip people off. For 100 years, BBB has been advising consumers: If it sounds too good to be true, it probably is.
High-pressure sales tactics, "limited time offers," prices that seem too low—all are tip-offs that something may not be quite right. Be especially wary of products that claim to help you lose weight without trying, settle a debt, make you rich, look younger, etc.
Another variation is rental or vacation properties advertised online; sometimes the property isn't what it looks like in the pictures, and sometimes it doesn't even belong to the person who just collected your deposit or rental fee. The owner says the place is yours if you wire money to cover an application fee, security deposit, etc. Once you wire the money, you never hear from the "owner" again.