I've had this car from new as a company car, and after the lease expired I decided to buy it at 3 years old for £5500 and about 16k mileage I think.
The car is now ten years old and going pretty strong if you ask me. Mileage has increased to 97k,

Work I've had done on the car:
Under the dealership, when it was a lease car, I only ever needed new tyres.
Clutch bearing was humming every time I put my foot on the clutch. My service guy said the bearing cost around £10, but it was best to change the clutch at the same time. So cost me about 300-400. Car was probably 5/6 years old at that point.
At around 5 years old I had a light on the dashboard for the airbag sometimes. If I turned the engine off and back on again it would go away. Eventually the light stayed on constantly. Around the same time the indicator stick would overcompensate when cancelling, and would often flick over from indicating in one direction over to the opposite after turning a corner. I read that this could be worked around by using a sponge (see youtube - comms unit)! I wasn't really bothered about the airbag light or the indicator, until the MOT rules changed, and the airbag light would lead to a failure! So after having the problem for 4 or 5 years old I had to replace the comms unit. The dealer said £300 for the part... OUCH. It cost me £300 for the part AND installation by going elsewhere.
My service guy said for 3 or 4 years running that my break pads were low and would need replacing the following service - then finally the next service I needed new pads and drums. Probably at 8 years old.
Put a new battery in it at around 7 years old.
at 9 years old the metal strap holding the exhaust on was corroded and soon would have fallen off.
at 10 years old and 95k mileage I had the cambelt changed - not sure what the other reviewer was on about saying that the cambelt would cost thousands of pounds to replace??? Crazy. Also the cambelt, I was told, doesn't need changing until 100k - not 75k
I have also had knocking sounds on the front nearside of the car. This was due, I believe, into a pothole at around 40mph. The knocking occurred during low speeds when reversing onto my drive (up a ramp) or when going over little bumps in the ground at low speeds. The problem was 'give in the ball joint' - so I needed to replace the 2 front arms at about £170. I had the knocking sound for probably 4 years, and not fixing it earlier probably cost me fuel and tyres (my previous service man never picked up this issue).

I've asked a service guy about whens a good time to get rid of a 206 - and he said that the 2.0 litre diesel has a good engine that will keep going. A shame its a bit small for a young family!

All in all, I'm happy a car that cost me 5.5k has lasted 7 years and not cost me that much with a yearly service.

Driving is good enough for my 20 mile work trip. The car is speedy enough, and handles well for me. Don't really have anything against it. It's never broken down. The bulbs for the main lights and beam are the same, and don't seem to last long. That's about it.