Just be careful with weekend markets many times it's the produce that didn't sell at the fruit / veg wholesalers during the week (I did some casual work at the wholesale market for many years, and Friday was clean out day)
My suggestion is buy stuff with the outer leaves on if you can, like lettuce, cabbages, collies, carrots, beetroot its an indication on the freshness. Ive seen some VERY sus produce trimmed to look very nice.