Revealing mistake: When Gabby and Fin are hanging off the building in Las Vegas, you can see that Gabby isn't holding on to anything in some close-up shots. (00:11:47)
Continuity mistake: Walter tore out the newspaper article ("Body of Woman Found at Greenland Rest Stop") fairly neatly/evenly; it was relatively straight across the top, though a little jagged as could be expected. When Walter looked at the article some time later, the jagged top was worse and there was MORE space between it and the title. The right side also appeared to be more jagged than it was and include a little more of the article that was to its right before being torn off. (00:07:03 - 00:13:37)