If you are staying at one of the hotels outside of Guaradalavaca i.e. Playa Pesquero, Playa Esmeralda or Playa Turquesa, make sure you take a taxi into town to see the Artists'market, where you will find local arts and crafts, T-shirts, jewellery and leathergoods.
Be sure to take your bathing suit, as the market is in front of the public beach which offers snack food restaurants, alcohol drinks and even live music. Also available there are rental sailboats and kayaks.
What to pay: You can afford any of it. Don't worry. Keep in mind, that whatever you pay the vendor, she/he will be handing over 50% immediately to his country (Direct tax)
Found an awesome little craft market just down the road from our hotel which appeared every day! Most of the crafts are very similar but you can find some really cool souveniour type stuff that helps to fund the locals.
Craft markets are spotted around all over the place! Even came and set up in our hotel a few mornings a week.
What to buy: Wood or soap stone carvings, beaded jewellery, gifts, souveniours
What to pay: Barter and get yourself a bargain, but remember that your cheap price is someone else's living money.