39. Duty chargeable on conveyance in part consideration of improvements
A conveyance on sale made for any consideration in respect whereof it is chargeable with ad valorem duty, and in further consideration of a covenant by the purchaser to make, or of his or her having previously made, any substantial improvement of or addition to the property conveyed to him or her, or of any covenant relating to the subject matter of the conveyance, is not chargeable with any duty in respect of such further consideration.