If you're feeling a little bit adventurous in Medellin and you want to find good bargains then go to El Hueco shopping district. It's easy to get there, take the metro to either Parque Berrio station or San Antonio station. From Parque Berrio you walk one block west along Calle Colombia and then make a left onto the pedestrian mall. From San Antonio station just walk under the metro one block west to Carabobo street (pedestrian mall).
El Hueco (The Hole) is a shopping district in downtown Medellin full hundreds of small shops that sell mostly clothing but you can find virtually anything from electronics to perfumes and shoes.
It encompasses several blocks in the downtown area but if you walk along Carabobo avenue (pedestrian mall) you can visit most of the large mini-malls located along this street. You should include Palacio Nacional (see photo). A large historic building turned into a mini Mall with hundreds of shops.
If you walk west from Palacio Nacional you can enter other mini malls where you'll find hundreds of little shops selling all types of clothing, you may get lost in those huge mazes interconnected with each other.
This is an area where bargaining is an obligation but prices are definitely very competitive and the quality of most clothing items is very good.
What to buy: Clothing in general, also footwear, swimwear. Household items.
What to pay: 10-50 dollars per item
El Tesoro Mall is a large Mall located on the mountain slopes of El Poblado in Medellin. It recently opened it's second level of shops.
It's the most upscale Mall in Medellin, but the best thing about this Mall is the breathtaking views it offers of the city from several points in the Mall, there are a couple of restaurants with those beautiful views, excellent place to enjoy dinner or lunch. There's also a wide range of fast food locales on one side and another section with more upscale restaurants. There's also a small amusement park for the children. And there's a cineplex too.
What to buy: Clothing, jewelry, books, perfumes, etc.
What to pay: Mid-priced to very expensive