Last Mile Design

I am not sure if this is a easy question to answer. But I am wondering what ISP's do for their residential and business customers for designing POP's that they usually access to get theur traffic into a given ISP and beyond. Is it usually a L1/L2 connection from the CE to the last mile POP? Or L2 even within the last mile POP. Do you just have POP's delegated to residential users and a separate POP for business users. Or is it done on a geographical basis. So for this region of City-A we manage both residential and business customers at this same POP.