NOT A TEACHER
(1) Of course, I take this question very personally!!!
(2) When you speak about my house, the "rules" call for
your pronouncing it "Jameses" house -- no matter how
you write it.
(3) Nevertheless, some (many?) native speakers would
refer to my house as "James" house if written as James'
house. My name, however, is "James," not "Jame."