O. Karl Ernst Foelsche
It's very situational. If the game was almost over and we needed a few more fortified locations and didn't have the moves to make it happen that could come in very handy!
Sometimes money is not super tight but movement is.
That sort of confirms my gut feelings about it. There seem to be much stronger buildings out there. (Like the horse cart.)
If you dropped the price to two, I doubt it would be overpowered. It might also see more use.