When to hold and when to sell?

[Paul Zofsak]

I am curious to see what strategies other investors use to determine when it is time to sell off some of their rental properties.  I don't mean when you need cash, or emergency situations, etc.; but at what point do you look at the numbers and say" time for this one to go, this one stays, etc...?

One of the real estate strategies that was taught to me was that you get all repairs, big and small, done in the beginning, roll it into the financing, and then sell after five years (supposedly when things start to fail and need repaired/replaced).  I would imagine there are many other strategies out there and I want to know more about them.