Welcome.
I like a "fixer upper". It gives you something to do and the chance to become familiar with your car as well as making it feel a bit more personal to you.
Personally, I've had a minor problem with scrap yards and these cars. We don't have too many scrappys around here. One deals with pretty poor condition vehicles, the kind that have been abandoned and picked up by the council etc. The good thing about this one is that you are allowed to go in and take the bits off for yourself and the prices are really low (as a new driver running my car on a shoestring while I was a student "back in the day" this place was a life saver). The other main one is a much more commercial organisation where you phone up, ask for a part and they take it off for you and generally charge you a cheaper-than-new-but-not-as-low-as-you'd-want price.
The problem? Despite there being loads of these cars on the roads, they seem to go on and on forever so I never see any of them in the cheap scrappy.

Just remember, that nearly all the important bits can usually come from any of the producers (Peugeot, Citroen or Toyota) and not an awful lot changed for many of the parts between the revamps/facelifts of the models either. It's generally only the bits that give the cars their individual styling that has to come from your specific model (with the Aygo, of course, that does involve quite a bit round the back of the car as well as the front but, like I said, an awful lot from across all models will still be fine.