Yeah, @aaron_flores84 made a good point about the metallic rattle versus the dull thump... but how do you tell when it's just normal wear and tear versus something about to break? I mean, sometimes the vibrations change slowly over time, and you might not notice until it's too late... do you have a trick for that? Like, do you keep a log of the sounds or something? Just wondering because on my site, the background noise can make it hard to pick up on the subtle shifts...

Is tree topping really that bad in the long run?

My AC was grinding for MONTHS and I just assumed it was dying. Almost called a repair guy which would have cost a fortune. My buddy came over, popped the cover off, and found a leaf stuck in the fan. Pulled it out and the noise stopped INSTANTLY. Now I always check the simple stuff first before panicking. Saved myself hundreds for five minutes of work.

Great, now even the rocks are clearer than my life plans.