How many movies have O Sing-Pui and Yiu-Cheung Lai collaborated on?

They have worked on 3 movies together! Their first movie together was F***/Off (1998) while their highest rated movie together was 春风得意梅龙镇 (1999). They have not worked together since Four Chefs and a Feast (1999). They are most known for their comedy films together.