I've only watched through season 1 and 2 once, so what are the smaller details that I've probably missed?

Someone was saying the other day that in the s1 ep where roger and don have to climb the stairs as the lift wasnt broke, that don actually paid the elevator guy to say that it was (revenge on roger for flirting with betty). apparently you see don handing the guy money just before he tells them the elevator is broken. i completely missed this.