Nice picture atop the article of a couple 964s which are NOT the "still simple 911" they are referring to when naming the 84-89 era.
50k to drive it for 10 years while its value remaining the same doesn't sound like a great value proposition to me.
DIY will help cut the cost in half, but it still does not sound like a good idea IMHO, unless you are a Porsche nut, of course.
G