On a search on mobile.de for bmw 3 series up to 2004, 90% of the returns are compact versions. What makes these cars cheaper than the normal versions ?
If l would have known l would not have asked the question ... right ?

Are you serious?
Do not you know that they have smaller engines, less stockier components, less bells and whistles, and are specifically targetted towards people who have less money?

^^^He said it all, they are underpowered too. Never buy a 323i, that thing is a MESS. They also use hubcaps on the 323i lol.

You're so lucky. Here in the States we have not seen a 3 Series compact since about 1999.

Cheaper? If you're referring to the used market value being significantly lower, I'd have to guess that it is a supply-and-demand issue. After all, you did say that 90% of the returns are compacts.

If you do get one, make sure you get a manual transmission. A stick helps make up for the missing torque.