N.H. Rev. Stat. Ann. § 452:4

Upon the expiration of 30 days from such notice, and within said 2 years, the vendor may pay or tender to the purchaser, or his legal representative, or, if neither resides within the state or their residence is unknown, into the town treasury of the town where the monumental work is located, subject to the purchaser's order, all sums the purchaser has paid in excess of 1/3 of the contract price.