The performance guarantee outlined in § 501-49 below shall be in a form and substance acceptable to the Board.
A. 
Before endorsement of its approval of a definitive plan, the Board requires that the construction of ways and the installation of municipal services be secured by one, or in part by one and in part by another, of the methods described in the following clauses A(1), (2), (3), and (4) which method or combination of methods may be selected and from time to time varied by the applicant:
(1) 
By a proper bond, sufficient in the opinion of the Board to secure performance of the construction of ways and the installation of municipal services required for lots in the subdivision shown on the plan, and the Board may require that the applicant specify the time within which such construction shall be completed. Bonds shall be issued by a company properly registered and licensed to issue bonds in Massachusetts.
(2) 
By a deposit of money or negotiable securities, sufficient in the opinion of the Board to secure performance of the construction of ways and the installation of municipal services required for lots in the subdivision shown on the plan, and the Board may require that the applicant specify the time within which such construction shall be completed.
(3) 
By a covenant, executed and duly recorded by the owner of record, running with the land, whereby such ways and services shall be provided to serve any lot before such lot may be built upon or conveyed, other than by mortgage deed; provided, that a mortgagee who acquires title to the mortgaged premises by foreclosure or otherwise and any succeeding owner of such premises or part thereof may sell any such lot, subject to that portion of the covenant which provides that no lot shall be built upon until such ways and services have been provided to serve such lot; and provided, further, that nothing herein shall be deemed to prohibit a conveyance by a single deed, subject to such covenant, of either the entire parcel of land shown on the subdivision plan or of all lots not previously released by the Board. A deed of any part of the subdivision in violation hereof shall be voidable by the grantee prior to the release of the covenant but not later than three years from the date of such deed.
(4) 
By a tri-partide agreement, as described in the Subdivision Control Law.
B. 
If the surety is to be a combination of a covenant and some other form of surety, the amount of surety required to ensure the completion of the subdivision improvements shall be calculated as the amount of money required to install improvements from the intersection with the existing way to the end of the last lot not covered by a covenant; lots covered by the covenant must be contiguous and divisible from that portion of the subdivision not under a covenant. If a turnaround is required to service any lot, the amount of surety must be enough to complete the roadway up to and including the turnaround.
A. 
The penal sum of any such bond held under Clause A(1) or any deposit held under Clause A(2) or any amount of funds retained pursuant to an agreement under Clause A(4) shall bear a direct and reasonable relationship to the expected cost including the effects of inflation, necessary to complete the subject work.
B. 
Such amount or amounts may from time to time be reduced so that the amount bonded, deposited or retained continues to reflect the actual expected cost of work remaining to be completed; however, individual lots shall not be released from a covenant until all municipal services and required improvements are complete up to that lot.
Requests for a partial release of surety must be made on Form G.
Requests for final release of surety shall be made in accordance with MGL c. 41, § 81U.