Visit the salon or club to see if the people are professional and friendly. Notice whether the establishment is clean and the equipment appears well-maintained. Examine protective goggles, as they can be a source of serious eye infection if not cleaned properly. Check to see if prices are posted and beware of high pressure salespeople. Confusing deals that sound too good to be true, are often just that.
Legitimate businesses are often happy to quote real prices over the phone.
Promotions are great, but slashed prices and cheap, long-term memberships may be a sign the business is in trouble. They may have good reason to be concerned with this month's cash flow, rather than next year's overhead. Or, want you to support their lifestyle in July-August, when fewer people tan in salons. Be sure the club or salon can service the memberships it sells. If an appointment is required or you cannot tan during convenient times, consider this a sign they may be overselling.