This set phrase is almost an idiom. Use this phrase and you're almost certain to trigger a smile on the face of the Chinese.
Depending on your bargaining techniques you may want to not use this while actually bargaining. Or you could say to the shopkeeper that you don't want to waste time bargaining over the price so you may just agree on a (cheap) price and give it over with.
Did you have a nice experience bargaining prices in China? Please in the comment section below.