Yes, you absolutely can buy good clothes in Nicaragua!
We have 4 big shopping malls, but besides that we have a lot of great stores scattered all around the city, in Managua.
I can name you some of the brand stores we have here like United Colors of Benetton, Tommy Hilfiger, Guess, Nine West and Steve Madden for Shoes, Hush Puppies for Men, Crocs Store, Us, Polo Assn., Moose, Kenneth Cole, and so many more. We also have a big department store where you can find everything and anything you may need. The store is called SIMAN and it is a department store in all Central America. It offers you all brands of clothing for both men and women like very nice and fancy suits, ties and shirts, blouses, etc, etc, to the best brands in colognes, perfumes and makeup for the ladies.
In that same store you can find items in all categories like electronics, furniture, entertainment, toys, sports, baby, home and optics, home, and so on.
As I mentioned before there are a lot of really good independent stores, scattered all around little plazas, that have really good clothes.
Also, as very good news to Nicaragua, not only because we get better options when shopping, but we also get a lot of job opportunities for the country, is that Walmart is under construction now, so you will have a lot of options for your clothing, either within an economical range, or expensive brand clothing.