I have worked retail. Some registers are too small for me to read the buttons and displays. And when someone's barcode or credit card won't work you'll need to be able to read the numbers to type them in. I was pretty good at stocking and displays though. Eventually I changed over to office jobs like data entry and reception where I could change the resolution and font to my needs. Pet sitting and dog walking were my favorite part time gigs if you can get them in your area.

Magnifier? Glasses?