If you want a thorough diagnostic doing on one before you buy, give me a shout.
Its quite easy for someone to plug in a cheap code reader to turn off the engine management light to hide a fault, but the diagnostic equipment I have reads the entire car's History
I was looking at a 106 for the OH. It had an airbag light on. The seller (a trader operating from his driveway) said that he'd knocked the wiring under the seats when hoovering a few days ago and it had just come on.
My diagnostic equipment showed that the light had been on for several thousand miles.
Look out for any dash lights not lighting up and going off - airbag and ABS ones are the most common ones that get covered over with electrical tape behind the dash.
Check that the display screen in the centre of the car is working - people disconnect it or pull out the bulbs to hide error messages.
Check the roof opens and closes OK. Roof faults are usually down to a broken or chafed wire.
Check that the leading edge of the boot liner screen isn't bowed.
There are plenty around, so shop around and get one with good service History
. Avoid diesel engined ones as they will only have been used for local short journeys and will have DPF and EGR problems.
Other than that, the 206 is a good car. You'll see lots of early models still running around which is a testament to their quality.