Get a complete description in writing of the work involved. Be wary of companies that want you to send them money before they put you to work. Be leery of companies that want you to pay for seminars or materials. Listen very carefully to the pitch before you bite. Some scammers will try to lure you into multi-year subscriptions costing hundreds of dollars.
Credit card offers.
Read the fine print. Low teaser interest rates expire after a few months. There usually is no reason to pay an annual fee, unless the interest rate is very low and permanent and you're carrying a high balance. In general, don't pay someone who promises to help you get a credit card. Beware of salesmen who offer a gold card or other such term.