When Mike shoots the man through the wall, there is no bullet hole in the wall.
The windshield of Walt White's vehicle is cracked from the inside, but the windshield is fixed with tape when the shot switches to the outside.
While following Gale through his apartment, we see a telescope. A reflecting telescope. The eyepiece on a reflecting telescope is at the open end. It is aimed at the inside of his apartment. So he has been viewing the walls of his living room, if it is able to focus that close.
When Mike shoots the man through the wall, the bullet comes out significantly later than when the sound begins.