Site improvement guaranty. A guaranty in favor of the Township in an amount not to exceed 120% of the cost of installation of only those improvements required by an approval or developer's agreement, ordinance, or regulation to be dedicated to a public entity, and that have not yet been installed, which cost shall be determined by the Township Engineer, according to the method of calculation set forth in Section 15 of P.L. 1991, c. 256 (N.J.S.A. 40:55D-53.4), for the following improvements as shown on the approved plans or plat: streets, pavement, gutters, curbs, sidewalks, street lighting, street trees, surveyor's monuments, as shown on the final map and required by the Map Filing Law, P.L. 1960, c. 141 (N.J.S.A. 46:23-9.9 et seq.; repealed by Section 2 of P.L. 2011, c. 217) or N.J.S.A. 46:26B-1 through N.J.S.A. 46:26B-8, water mains, sanitary sewers, community septic systems, drainage structures, public improvements of open space, and any grading necessitated by the preceding improvements. The Township Engineer shall prepare an itemized cost estimate of the improvements covered by the performance guaranty, which itemized cost estimate shall be appended to each performance guaranty posted by the developer. In the event that other governmental agencies or public utilities automatically will own the utilities to be installed or the improvements are covered by a performance guaranty to another governmental agency, no performance guaranty, as the case may be, shall be required by the Township for such utilities or improvements.