Look for higher quality, not brand or model. On the bike above, claw RD hanger, steel chain rings, stem shifters, steel rear rim, nutted axles, turkey levers, no lever hoods, all typical signs of low, low end. Probably has steel handlebars and seat post too.
Commuting for beginners? A rigid frame MTB can make a fine choice.
Most of the well known vintage brands made a full line of bikes, from really low end to top of the line. And of course, they sold a lot more of the low end bikes, so there are more of those out there today. Being able to spot the difference is key to making a better decision. And on older bikes, they typically require maintenance work, which can easily consume your budget. People rarely maintain their bikes. And some resellers do less than complete jobs of refurbishing bikes they sell. Its not unusual to see the easy cosmetic stuff done (like the bike above) while the stuff you can't see is ignored. Being able to spot the difference is important.