Our ceiling fan has worked perfectly up until last week. It will not turn on at all. How can we troubleshoot to determine the cause before we spend lots of $$$? It is a Harbor Breeze brand (model# 271009) we purchased from Lowe's.

If remote, check batteries, verify codes.
If Hardwired check for power out of the switch, then check for power under the canopy. Check pull chains for a click. And check the direction switch is not in the middle.

Ditto