The level of champagne in Walt's glass stays the same even though he takes three drinks out of it.
When Marie is at the spoon house, the realtor says there is a sizable attic, but the establishing shot shows a one level house.
Walt & Skyler celebrate the planned purchase of the car wash by drinking from a $320 bottle of Pol Roger Cuvee Sir Winston Churchill Champagne. Skyler asks "How do you, Walter White an unemployed school teacher pay for it? How do you explain it?... On paper we have no money." Yet they are about to buy a business for $800,000.
When Marie is admiring the spoon collection, the realtor says that there is one for each state, and Marie points out that Puerto Rico is a territory. This would indicate that there are 51 spoons. There are actually 54 in the display case.
Near the end when Walter and Skyler are drinking Champagne - in the mid shot of Walter during their conversation - a light can clearly be seen reflected in Walter's glasses. No light, window or shape of that kind is present in the wider shots.
While people are partying at Jesse's house one of them hits the camera with his head.