Yes, it has a timing chain. One of the reasons I bought one.
When you test drive it, you may be concerned that the clutch bite is quite high. Rest assured that the bite is high on all gearstick shift Aygos. Check the boot for any signs of water ingress into that area. I believe some Aygos of that era can leak elsewhere, but I can't remember exactly where. Maybe another member can help out here.
Oil level can be a pain to check, especially if the engine has been running recently. Take some kitchen roll along to wipe the dipstick, as you may have to check and dip a few times before you get a satisfactory reading.
Also, I've found the steering to be a bit sticky around the straight ahead position. It's the same on two Aygos in the family, so think it's an Aygo character. Obviously, if the steering doesn't return at all to centre after a turn, then be wary.