書呆子？多少房子才能寫出“概率”來？

I believe the rent goes with the market. If you increase 10% yet the market had risen 20%, you will get by. Try answer this one :"Why they want to pay more to you not others? " It wouldn't matter what kind of house there is.

If the market drops, you might just get lucky not have to.

There shall not be any formula, or past experience that would guarantee a correct answer. There should be no answer for all such questions at all.

The sense of doing business makes the difference between who can succeed and who can't.