Do you know you can buy them on refurbishment platforms like Backmarket ?
They have a warranty up to one year, and any problem is resolved pretty quickly.
It’s not as cheap as trying your luck in the various 2nd hand sites but if you value safety and time it’s worth it.
It still comes out much cheaper than anything brand new.
I bought quite a lot of phones on those platforms and the only time there was an issue (faulty touch layer on a display side) it was swapped within 3 days.
It’s irrational fear really. If anything those phones are rock solide because if they survived the first few years of their lives, unless there is an event they are very likely to have a long life (no faulty part, pre-tested); the only care is battery life if that wasn’t changed during refurbishing.
But generally people who can benefit from those phone do just fine pushing the battery to the very end of its life so it doesn’t even matter that much.
A non trivial amount of those phone end up there because they are fully financed after 2 years and the owner gets a new one. Sometimes you find one year old phone that were just swapped for the newest one because their owner is rich enough that he can’t be bothered to do a battery replacement and would rather have the newest model.
Some people are rich and many don’t have that much financial responsibility, people should take advantage of that, just saying…