Section 5617 - Certain testimony authorizedIn all proceedings arising from the exercise of the right of eminent domain, it shall be competent for all witnesses called, when duly qualified:
(1) To state in detail and costs all the elements of the property before the exercise of the right of eminent domain and as unaffected by it and its market value immediately after the exercise of the right of eminent domain and as affected thereby.(2) To state in detail and costs all of the elements of benefit or damage which they have taken into consideration in arriving at their opinion.(3) In arriving at their opinion as to the market value immediately after the exercise of the right of eminent domain, to add to their opinion of the market value before such exercise the cost or value of all the elements of benefit or advantage and to deduct therefrom all disadvantages or damage in order to arrive at the market value after such exercise of the right of eminent domain and as affected thereby.(4) In all proceedings to assess damages or benefits for the opening of any road or highway, to take into consideration as one of the elements of advantage or disadvantage the cost of highway improvements.1953, July 28, P.L. 723, art. XXVI, § 2617.