Ok, in response to your Dads "issues"....
squeaky brakes - a common fault with the 206cc - should be fixable with new brake pads (probably best off with non Peugeot ones).
the rattling noise you describe could well be the exhaust manifold that again is known to crack. Mine did pretty much as soon as I got my car but it was replaced and was fine afterwards (some people on here have gone through 2 or 3 though!). The manifold will be replaced free under warranty so no problem apart from the inconvenience if it keeps needing to be replaced!
The roof is noisier than the SLK - but what does he expect it's cheaper!
The ding noise doesn't always work. Mine didn't always ding but I never had a problem with the roof getting stuck, not working etc
Yes there are quite a few squeaks and rattles but hey when the roof is down who cares

Most of the squeaks can be cured by regularly using some lube on the roof/window seals. The rattles can be fixed by turning the stereo up
I'm glad I owned my 206cc for a year or so but I don't know if I could've stuck my Dad saying 'I told you so' everytime I took it back to the Dealer to be fixed.
Have you been for a test drive in an A3 yet?