I finally asked a stranger a dumb question at a hardware store in Cleveland and it saved me $200
So I have been trying to fix a squeaky floor upstairs for about 4 months now. I watched maybe 15 videos and all of them said to just sink a bunch of screws through the subfloor from below. My problem is I have no basement access under that part of the house, it is a finished ceiling. I kept thinking I needed to buy one of those $200 screw jacks and cut a hole in the drywall. Last Tuesday I was at a small hardware store on Lorain Ave picking up wood filler and I just asked the older guy at the counter if there was any trick. He said "shim it from the top through the gap under the baseboard, you do not need to go underneath." Took me 20 minutes with a $4 pack of cedar shims and the squeak is gone. I had been overthinking it for months because nobody on YouTube mentioned the baseboard gap. What is a fix you almost paid way too much for until someone just told you the simple way?