Continuity mistake: When the yeti takes the air conditioner and the cousin calls the police, it goes from daylight to night time in seconds.
Other mistake: When the characters go to the Himalayas, the whole time, like for 20 mins, including the confrontation scene, they are all wearing casual, short-sleeved shirts. You can see Mr. Burnish's henchmen wearing winter clothing, while the main characters don't freeze to death. They only start getting cold after a long time.