Unpopular opinion: the $2 mirror I got at an estate sale in Dayton made me faster than any brush I own
Was sweeping a rental off third street back in March and the owner had a box of junk by the curb. Grabbed a little inspection mirror with a telescoping handle for two bucks. Used it to peek up past the smoke shelf where I used to go in blind. Found a cracked flue tile on that job in about ten seconds. Now it rides in my front pocket. What cheap thing did you grab on a whim that ended up in your kit?