N.H. Rev. Stat. § 479-A:22
All sums assessed by the association of unit owners but unpaid for the share of the common expenses chargeable to any unit shall constitute a lien on such unit prior to all other liens except only (1) tax liens on the unit in favor of any assessing unit and special district and (2) all sums unpaid on a first mortgage of record. Such lien may be foreclosed by the manager or board of directors, acting on behalf of the unit owners, in like manner as a mortgage of real property. In any such foreclosure, the unit owner shall be required to pay a reasonable rental for the unit if so provided in the bylaws, and the plaintiff in such foreclosure shall be entitled to the appointment of a receiver to collect the same. The manager or board of directors, acting on behalf of the unit owners shall have power, unless prohibited by the declaration, to bid in the unit at a foreclosure sale and to acquire and hold, lease, mortgage and convey the same. Suit to recover a money judgment for unpaid common expenses shall be maintainable without foreclosing or waiving the lien securing the same. Where the mortgagee of a first mortgage of record or other purchaser of a unit obtains title to the unit as a result of foreclosure of the first mortgage, such acquirer of title, his successors and assigns shall not be liable for the share of the common expenses or assessments by the association of unit owners chargeable to such unit which became due prior to the acquisition of title to such unit by such acquirer. Such unpaid share of common expenses or assessments shall be deemed to be common expenses collectible from all of the unit owners including such acquirer, his successors and assigns.
RSA 479-A:22
1965, 155:1, eff. Aug. 14, 1965.