Wal-Mart is the best bet for buying most liquor.
Bartering is a must. Buy your silver on the beach. Cut the price in half of what you would expect to pay and then go lower. Bracelets should go for US$5 for thin and US$10 for somewhat thick silver.
Don't do the all-inclusive if you want to catch a buzz. Buy your tequila from the liquor store when you get there and add it to your drinks. Mexican beer is only 4.5% alcohol so you have to drink about 4 beers to get an inkling of a buzz. Kahlua is dirt cheap at only $7.
Do as many tours as possible. Buy your tours downtown, not in the hotels. They're half price of what they cost there. Barter, barter, barter, and then walk away!
If you have a rainy day, do a timeshare presentation and get what you want from the deal. You'll get the deals, no strings attached.
All the tours are on luxury buses. You can't lose. The Mayans go out of their way to please you. Tourism is their #1 source of income. Just when you think you bought enough, buy more.
You won't believe how cheap everything is. Most retailers won't accept credit cards. Use your pesos because it means better bartering. The U.S. dollar is worth more and can be confusing.
Cash out your dollars at the bank not the hotel – it’s your best bet for a higher exchange. Bring your passport though. Banks are only open for exchange from Mon-Fri 9am-2pm.
Clubs don't open until almost 2am! We went as late as midnight and they still were kind of dead. If anyone knows where the single scene for mid 30s and up, tell me. All that we saw were families and young kids. If you were 16, you were prime age for the singles scene during the Christmas season.