What is an inexpensive replacement for these garage flourescent lights?
https://s13.postimg.org/7jivra81j/garage_lights.jpg

There are four of these sets of lights, each of which holds 4 flourescent
bulbs, which keep flickering, burning out, and making humming sounds.

In a word, they suck.

So, instead of replacing the bulbs for the rest of my life, is there a good
but inexpensive quick and simple replacement strategy?

That is actually a 2'x4' lay-in fluorescent fixture. There are LED retrofit kits available. I would get a retro kit that does not use the existing ballast. As far as quick, cheap, and simple, you will have to make your own determination.

John Grabowski
http://www.MrElectrician.TV