One of my favourite things in Korea is the chicken van.
The chicken van man is exactly what it sounds like: a man who drives around with a van full of chickens. The key thing to point out is that the chickens are already dead, and located in the back of the van, slowly cooking rotisserie-style. The van is specially made to cook chickens. The chickens are often whole and stuffed with fried rice.
The chicken van man usually appears in the evenings, from around 6pm onward as everyone makes their way home from work. He will park in a choice location and sell out of the back of his van.
There is no one rule as to where they appear. I tend to wander around the neighbourhood and buy one if I find it. They are generally located close to but not in busy areas. Sometimes they are not far away from high streets or subway stations.
The prices don’t vary too much, but the deal you get depends on the location and the quality of the chicken. Usually the chickens are slightly anorexic, but there is always some good eatin’ on them. The lowest price will often be 4000-7000 won ($4-7) for one. The best deal I saw was 10000 won ($10) for 3 whole chickens, but you will normally get 2 whole chickens for that price, which is still a fantastic price.