I doubt anybody is willing to pay 900$ for that bike. It isn't worth 900$ even if it was NOS. If you live in big city, you could get lucky and sell it to some hipster for 350$. Why does the bike have a relatively modern claris derailleur?
I'm pretty certain that this is just your generic run of the mill old road bike, it's not vintage... It's just old.. For some reason normies love Peugeot, probably because its a brand they recognise and its french. My girlfriend wanted one, my old flat mate wanted to convert get and and convert it to a fixie....etc
THIS is a vintage Peugeot and is worth 900$. Do you see the different in quality? I'm not saying your bike is bad, but it is objectively completely shit compared to a a modern entry level road bike for example...the Trek Domane AL 2 or a Giant Contend 1 which can be had for around 900$..