In making appraisals it is customary to adopt units of measurement differing from those for ordinary real estate plots. For land under water the unit is the square foot, for bulkhead rights the running foot. In regard to pier rights the units of measurements differ according to the special circumstances governing the case, as, for example, whether bulkhead rights go with the pier rights, in which case the unit would generally be the square foot of controlled area; in other cases the lineal foot of water-frontage occupied, or the lineal foot of wharfage room; in other cases still, the square foot of pier area, etc. All units may be given a very greatly added value through what has heretofore been explained as the conjunctive value, and for other reasons, for example, whether or not there is a right to shed the pier. The location of the pier and many other points have to be considered, including the legal character of the rights in each particular instance.