You say this as if the principle of the matter is of no importance whatsoever. That's utterly contemptible.
It is of no relevance what the statistical average is for people staying in one place. Screw the statistical average. Statistical averages is what leftists use to deteriorate our Constitutional rights. It's her home, her property. She, not Costco, is entitled to decide how long she wants to live there and bloody hell if she has justify why.
The city could recoup it's investment - at her asking price - in one year. Not a bad deal. Source