so much of the stuff I bought from markets was junk.
Thats why it's (supposed to be) cheap.
I was only stung once at one of these markets. When I bought a DVD-ROM drive that never worked (I found out later that I wasn't the only one who was stung by the same stall) turns out the stall was only there for one night and sold everyone crap. They were never seen again ( and I hope I never do cos I will more than likely stick said drive up where the sun don't shine)
Here's a few rules when going to these places.
1) Get the shows guide when you enter the market it will give you information on safe buying and what rights you have (if any).
2) Always get a receipt and some form of guarantee ( with a contact number )
3) Only buy goods from people that are there on a regular basis.
4) If you know what your looking for get a few prices from your local computer store (you may find them cheaper than the trader at the market and a lot less hassle if it turns out the goods were dodgy)
As a personal rule I only buy consumables (Printer Ink/Paper/DVD-R's). I did break this once and came up trumps with a 4GB USB memory stick.