I've been doing the painter's tape / Sharpie thing for decades. But they do fade and/or fall off eventually.
Label maker seems like a good idea - might get myself one.
I don't put the make/model/year on them, just each guitar's given name.
Of course, when I take one out of the house, it's normally in a gig bag.
I have a couple of molded universal type hard cases that I used to travel with.
They're marked with brightly colored tape, but not labeled as to the contents.