It is easy to think that you are getting great deals on items you would normally pay three times more for back at home, when really you are paying for items three times lower in quality. You have to be careful on which products you get for bargains.
Markets, especially in South East Asia are often swarmed with traders trying to sell reduced price iPods, cameras and mobile phones. The price may look good but you have to consider the quality of the product on offer. There is a reason why electrical items are marked so low on stalls; it is because they are either damaged, have lower battery capacities, have firmware malfunction or are just cheap imitations. Do not buy expensive electricals off stalls unless you have a good eye for quality and can test the item. If your request to test is refused, then walk off straight away. If you decide to take a gamble then make sure the product on the box is the same as the one in the box. It is not unheard of for items to be switched for cheaper, lower spec models of the same thing or an entirely different product all together.
Having said this, you can get very good deals on electrical accessories such as headphone, travel speakers, camera tripods and adapters. These items are much cheaper to buy and therefore minimal risk. I bought a new pair of white iPod earphones in Bangkok and they have lasted longer than the originals and cost a fifth of the price of a replacement from the Apple Store. Have a sharp eye about you and use your judgment; I mean, you would not buy a top of the range laptop off some guy in the street in The UK or USA.
As far as DVDs are concerned there is potential for you to triple your collection for a fraction of the price if you are happy to exploit the production companies by supporting the counterfeit market; they are all fakes. If you do decide to buy, firstly ensure the DVD is for the correct region. Some stalls offer discs that are multi region which is even better but your major concern should be picture quality. There could be nothing worse than watching the latest blockbuster looking like it has been recorded on your mobile. In shops you can ask if you can play the disc before you buy but again, be careful of a switch. Ensure that the play the disc you give them and not another disc that has been preloaded. As a guide, you can judge the quality of a movie by its release date. If a film has just been released in the USA, you can count on the DVD quality to be a very poor, cinema recorded replica. Other films it can be hit a miss, but as a rule, 6 months old releases and earlier would be a safer bet.
You can be sure to find many local crafts being sold such as wooden statues, woven bags, jewellery and assorted other things depending where you are. These can be a really good buy as they are often hand made and high quality, unique as they cannot be found at home, and generally make excellent souvenirs. I encourage you to buy crafts as they capture a piece of culture and help support traditional skills and methods of manufacture. However, still think before you buy. Decide whether an item is too fragile to carry for the remainder of your journey or too big and heavy. Be sensible with what you buy and if you are considering buying and then sending an item home by mail, use sea freight which does take longer but is a fraction of the cost of airmail. Secondly, do not buy crafts made of untreated wood because customs will confiscate it. Untreated wood can carry pests or chemicals not permitted into other regions. Remember to always declare the craft if you are not sure to escape being cautioned or fined.
Tourists also go mad for clothes in markets. There are always many deals on t-shirts, fake bags and fashion accessories. Many people will go with a half packed case, have their first stop in Bangkok and continue on with a whole new wardrobe. You must remember that what you are buying is almost definitely counterfeit and may have to be cleaned on a low temperature wash to avoid shrinking. However, I would urge to buy t-shirts and towels cheaply as at that price it does not matter if you lose or ruin them, or they make great gifts.
Men may get offered suit fitting by tailors while walking down the street. They will give you cards and try to entice you into the shops. I have heard of people getting very good deals but again the suits had to be carried for the rest of the trip. I have been told you have to be firm with the shopkeepers as they will try to sell you everything in the shop even if you only went in for tie, but if you play it right you can come out on top.
Spend your money wisely and on things that are practical and useful for the rest of your trip. By all means buy things you would not normally but use your judgment on the price tag and have a sharp eye.