BikeTales 

Helping someone out. It definitely has a 501 label, and the pearl white color and decals seem to match to an 83. Bike is in Canada.

Has seen some use, and is in "20-years-in-a-barn" condition (i.e.: needs tires, tape, the usual.)

I didn't find much as far as previous sale prices. It's in Winnipeg.

Assuming nothing is broken, what would you ask?

ramzilla

If it's in decent shape & nothing is missing you might get $100 without doing a thing. Now, if you put some elbow grease into it, rebuild the bearings, shine the frame, new chain & tires....... maybe $200.

BikeTales 

Thanks @ramzilla Here's a photo for the heck of it

Imgur: The most awesome images on the Internet

Chombi1 

Actually, that bike's in pretty good condition and looks like it was hardly used. It should clean/tune up really nicely.
In a hot market, a bike like that could bring in close, or even up to 300 bucks cause it has all the things that defines a good quality C&V bike.
A well known/established marque (Peugeot is well known for providing very good ride characteristics and strong, reliable frames), Reynolds tubing, fully lugged frame, forged dropouts, nice chrome touches, classic graphics and nice paint color, nevedentrust, popular size (54 or 56cm), complete, original components (only thing that seem to maybe be non-original is the rear wheel).
A great barn find! Glad that it was saved before it started to deteriorate.

ramzilla

It's not in rideable condition. So, that's going to take a little work before you can expect much more than around $125. Put about $75 - $80 new parts on it (tubes, tires, chain, bar tape, brake pads) + do the work yourself & get it in ride worthy condition & then maybe you could score $300. Be good.