My work is usually custom, with odd sizes or patterns, so I usually build the cabinet or access doors.  I sometimes will build the entry doors.  

I built this closet, window seat and the entry door to match other doors throughout the house.

I opened the wall, built the 3 panel entry door and louvered door and trimmed it to match the existing.

I built this wooden screen door to match the existing entry. 

I also will cut holes in walls and install jambs casings and doors.