Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 80, § 13B

(1) that no sale or transfer of such real property may be consummated unless the betterment assessment which would otherwise have been collected on such real property has been paid, with interest as applied in accordance with the provisions of section thirteen;

(2) that upon the demise of the owner of such real property, the heirs-at-law, assignees or devisees shall have first priority to said real property by paying in full the total betterment assessment which would otherwise have been due, plus interest; provided, however, if such heir-at-law, assignee or devisee is a surviving spouse who enters into a betterment assessment deferral and recovery agreement under this section, payment of the betterment assessment and interest due shall not be required during the life of such surviving spouse;

(3) that if the betterment assessments due, plus interest, are not paid by the heir-at-law, assignee or devisee or if payment is not postponed during the life of a surviving spouse, such betterment assessments and interest shall be recovered from the estate of the owner; and

(4) that any joint owner or mortgagee holding a mortgage on such property has given written prior approval for such agreement, which written approval shall be made a part of such agreement.

In the case of each betterment assessment deferral and recovery agreement entered into between said board making the order for the assessment of a betterment and the owner or owners of such real property, said board shall forthwith cause to be recorded in the registry of deeds of the county or district in which the city or town is situated a statement of their action which shall constitute a lien upon the land covered by such agreement for such betterment assessment as has been assessed under the provisions of this chapter, plus interest as hereinafter provided. The statement shall name the owner or owners and shall include a description of the land. Unless such a statement is recorded the lien shall not be effective with respect to a bona fide purchaser or other transferee without actual knowledge of such lien. The filing fee for any statement recorded on behalf of a board of the commonwealth shall be paid by the owner or owners of such real property. The filing fee for other such statements shall be paid by the city or town and shall be added to and become a part of the taxes due.