In the "The Beauty Contest" Mayor Pike is talking about his wife in the barber shop and you can see Floyd in the background saying Dick Elliot's(Mayor Pike)lines.

in another episode-I forget the name, but it's the one where Andy hires an intern to work in the sheriffs office-in one scene the intern and Andy walk in the front door of the courthouse; through the left door. Then the veiw switches to the inside as they're walking in-only now it's through the left door again! (it should be the right door)

When Barney tries to recite the Preamble to the U.S. Constitution to Andy (I think that was the document), Barney's hair becomes messed up -- but in his close-ups that are interspersed, his hair is in place perfectly...!

In Keeper Of The Flame (2-14) when Jubal Foster is calling Opie a thief Andy comes to talk to Jubal when he crashes into Don Knotts.

in the Christmas episode, Ben Miller is seen looking through a window on the side of the courthouse, but in the shots of the front of the building there isn't a window on that side-the neighboring building is butted up against it.

In "The Guitar Player" James Best is playing an acoustic guitar, but has a sound of a electric guitar

In "A Wife for Andy", when the women come to Andy's house, 12 women enter, but only 10 leave. Note: TV Land edits out 3 of the 12 that enter.

Also, this is probably more of an inconsistency than a goof. Andy has an extra bedroom available for Gomer Pyle, Otis Campbell, Henry Wheeler and others, but not for Malcolm Tucker.

In "The Guitar Player" James Best is playing an acoustic guitar, but has a sound of a electric guitar

Good catch...