@bill345 For the first few months of using my CR-10-V3 (with glass bed) I used methylated spirits, which was good for removing contaminants, but also left a slight residue.
I bought some IPA (Isopropyl Alcohol 99.9% Pure IPA) about 2 months ago and I've only needed to use it twice. Once you have de-greased and cleaned with this stuff, you can just print & print & print (...as long as you keep your fingers off the bed!).
Firmware Upgrades; it seems to me that a very large percentage of questions on this forum concern problems following attempted upgrades. Just leave your printer as it is and print, print, print! That's what it is for!
Although I was given a BLTouch, I have absolutely no intention of fitting it. Its not difficult to level your bed, and once its done, leave it alone and just print. Only go back and fiddle with it if you are getting problems. I can't talk about all Creality printers, but my CR-10 seems very stable, and doesn't need continual tweaking.