§ 26-b. Just compensation as including loss of mortgage financing. Notwithstanding any inconsistent provisions of law, whenever property is taken pursuant to the power of eminent domain (whether denominated condemnation, appropriation or otherwise) just compensation required by the state constitution shall include an amount sufficient to compensate for the loss of existing mortgage financing if such property was used prior to taking primarily as a residence however, such amount shall not exceed fifteen thousand dollars. In computing the amount of such loss, the following shall be considered: (a) the difference in the interest rate payable on the existing mortgage from that prevailing at the date of taking in the area where the property is located for new mortgage loans on similar types of property to similar borrowers; (b) the length of time from the date of taking to the maturity of the existing mortgage, and (c) the prevailing costs to similar mortgage borrowers on similar types of property at the date of taking in the area where the property is located of obtaining and closing a new mortgage loan in an amount equal to the unpaid principal balance of the existing mortgage.