The patrol car in the opening scene is a Buick Century, shown from various angles. In an overhead shot (the one with the LAPD black & white present for some reason) the NYPD car is instead a Caprice Classic.
The windows on the outside of Mr. Bernard's office do not match the window scheme on the outside of the building.
Though ostensibly shot in NYC, with some "on the by and by" clips shown in Manhattan, many of the outdoor action scenes were clearly filmed in the Los Angles California area. Noticeable in many episodes. The buildings, the street signs, and other props make this noticeable. This is especially true in scenes involving car chases. On one establishment street scene in 'Money Back Guarantee', viewing the street from above in a building, a black/white LAPD AMC Matador police car can be clearly seen in the same scene an "NYPD" Buick police cruiser is in.