Be very careful. Some owner built boats are exquisite and constructed way beyond what any factory could afford to do. Others are built by people with no practical knowledge of the sea or how to build a boat. Each one will be different, each one needs to be carefully inspected.
We built a Westsail 32 from a bare hull
. My hand is in one of the pictures in Ference Mate's first book. Almost all the W32s being built around that time were better than the factory boats though a few had really nutty interior
layouts. Have seen other W32's that have been poorly constructed and would have to be gutted and started over.
Check them out, you may find a jewel or a turd.