I have the opportunity to buy a Daewoo AR-100 for aroiund $1000.

What is the opinion of these rifles?

It has a side folding stock,flash-hider and bayo lug.
It looks in very good shape.

Thanks.

Excellent rifle, very fair price.

Sounds good.

Where do you get spare parts? Where do you get them 5 years from now? 10 years?

IMO, for $1000 you could end up with a very expensive paperweight.

Spare parts can be problematic.  I will buy a second DR200 for that very reason.  All I can tell you is this, its been close to ten years since these came into the country and a lot of folks shoot the piss out of theirs and they keep running.  FCG is AR15.  Firing pins can be crafted by any talented gunsmith as can extractors etc.  Bolts and carriers are available albeit expensive on places like gunbroker.  For a rare preban $1,000 is a steal even if you are just going to buy it for resale later.