This question does get asked a lot, and the honest answer is, it depends where you go.
Of course you will pay a little more to *** your goods locally but your paying for the convenience and these smaller stores cannot compete with the bigger ones as they *** in larger quantities.
Things that are not cheap in Brazil are cell phones and cars. If you get the opportunity to purchase a cell phone outside of Brazil i would certainly make every effort to make that happen as you will save substantially.
With regard to cars, you haven't really got an option when it comes to buying in Brazil. If you tried to import one there are certain rules that must be followed, and the main one is the car must be brand new. Along with that you will pay a substantial amount of tax on your import. So coupled with the taxes and shipping charges you just might as well *** one in Brazil. Another rule is, if the car is over a certain age, again think of all the taxes and charges you need to pay to get it there.
Domestic good prices in Brazil do seem to rise quite frequently so it does pay to look around and go to the best value supermarket where they do give offers.
Beef is a commodity which does go up and down in price. The best cut in Brazil is for aged piccania, which is just wonderful on the barbecue, but must be done right though. Lamb is one of the more expensive meats which although found in most places is not a favored dish.