Before sending SMS to short numberand you need to see the exact cost of such services. In most cases advertising of any service displays significantly understated the cost of an outgoing message. To balance your cell phone is not left at a huge disadvantage, call the customer service of your operator of cellular communication. After connecting with the Manager, tell him a short room and ask the cost of the outgoing SMS messages. If the sum converges with seller's price the messages in the ads, you can send an SMS (if you must). If the real value of the message exceeds previously announced price, it is better to refrain from sending SMS to this number (you run the risk of incurring significant losses, usually these scams are not limited to one message).
After you specify the cost of sending a SMS message to a specific short number, not in a hurry to take up the phone. Try as much as possible to carefully examine all the points of the user agreement (usually on sites it is marked as "User agreement"). Yes, you have to read a lot of information, but the only way you can avoid possible financial losses in the future (some services after send SMS messages are processed on subscriber's paid subscriptions without his knowledge, for which in the course of the month with the balance of the phone will be charged a certain amount).