The fact you may find a wrench to fit the fixed cup does not mean it will work. Even a closed-end wrench can easily slip off under the pressure required to remove a fixed cup. Google "remove fixed cup" to see the various options for dealing with it. It's also not a good idea to put money into a wrench you may never need again. As for the adjustable cup, it's probably corroded - you need to spray on some sort of penetrant and let it sit, then just grab the cup with vise grips if a regular wrench does not work - probably in bad shape anyway so no big loss, as you can replace with a cartridge BB.