A: Why are you cutting into the wall?
B: I bought a new air conditioning unit.
A: I don't think that's how you install it!
B: Have you ever installed one before?
A: No, but that still looks wrong.
B: I think I know what I'm doing.
A: I see water pipes behind that wall.
B: I don't think that's good for the air conditioner.
A: I don't think so, either.
B: Will you call some professionals now?
A: I guess that's the best thing to do.
B: You should have done so from the beginning!