(c) "Consideration" means in the case of any deed, the actual amount of money and the monetary value of any other thing of value constituting the entire compensation paid or to be paid for the transfer of title to the lands, tenements or other realty, including the remaining amount of any prior mortgage to which the transfer is subject or which is to be assumed and agreed to be paid by the grantee and any other lien or encumbrance thereon not paid, satisfied or removed in connection with the transfer of title. The amount of liens for real property taxes, water or sewerage charges for the current or any subsequent year, or by way of added assessment or other adjustment, as well as of other like liens or encumbrances of a current and continuing nature ordinarily adjusted between the parties according to the period of ownership shall be excluded as an element in determining the consideration, notwithstanding that such amount is to be paid by the grantee. In the case of a leasehold interest for 99 years or more as defined in subsection (a) of this section, the consideration shall be in the amount of the assessed value of the property at the date of the transaction for the purpose of levying local real property taxes adjusted to reflect the true value in accordance with the county percentage level established for the current year.
In the case of a proprietary lease of a cooperative unit or assignment thereof as defined in subsection (a) of this section, the consideration is the total price paid for the ownership interest held in conjunction with a cooperative unit, including the pro rata amount of any underlying mortgage or other obligation of the cooperative.