One other thing that's been mentioned before is the wild weather swing. One day was chilly and rainy (I think Columbo actually said in the 40s) and then within a day or two, the temperature soared to over 100.
I couldn't get by the first and second points, let alone the fact that rigor mortis would have made the stinky task just about impossible, but if we were to nitpick over every flaw in these productions, there would be no way to enjoy the show. There's nothing wrong in pointing them out for the sake of forum discussion, but I think we can all agree that every episode sports inconsistencies from reality.