The real trap is buying from Spanish or European reseller shops that mark up the price 2x or 3x compared to Japan. You're right to point at AmiAmi and Good Smile Company directly, but customs in Colombia is way more complicated than in other countries. My recommendation: use a Japanese forwarding service (like Tenso or similar) that receives your purchases in Japan and then ships them to Colombia; it costs about the same as direct shipping but you have more control over the packaging and sometimes options to consolidate multiple orders into one, which cuts costs.
Play-Asia is still a good option for certain figures, though not all of them. What I'd do is wait for deals to pop up during specific times (year-end, stuff like that) on shops like Hobby Search or even check auctions on Mercado Libre Japan if you know some Japanese or use a translator. The thing is to be patient: a Nendoroid that costs 1000-1200 yen in Japan easily becomes double or triple the price in Colombia if you buy it from here.