I second this suggestion. Note though that you either need to have a good idea what you're looking at when it comes to bikes or have folks who know what they're looking at either check the listing or, ideally, go with you to look at it in person. As is already obvious, you'll get a wide range of opinions on what's best here on the forum but I have a good feeling that if you send us some links, you can get a general consensus of if a given bike is worth it or not.

A good friend was looking to get his first road bike a year and a half ago. He was shopping for new bikes and was asking my brother and I advice on what to get. We told him to look for slightly used bikes and given it was a couple year into the pandemic, it was the perfect time to pick up a bike someone got during the pandemic bike boom, road twice and never touched again. Sure enough, he found a 1 year old mid-level Specialized with decent components and maybe 30 miles on it for half of what it sold for new.

We're still in that time where people thought they'd get into biking during the pandemic, bought a nice one, discovered it wasn't their thing, and want to get rid of the bike.