Whenever any such building, canal, turnpike, railroad, or other improvement shall be subject to sale under this chapter, from and after the filing of any complaint under § 34-28-10 and § 34-28-13, any contractor who shall not have fully completed his or her contract in relation to the erection, construction, alteration, or reparation thereof, shall thereafter be excused from completing the contract, unless unreasonable conduct by the contractor has contributed materially to the facts giving rise to the filing of the complaint (in which case the person contracting with the contractor may at his or her option excuse the contractor), but the excuse from completing the contract shall terminate if and when the building, canal, turnpike, railroad, or other improvement and the land on which the improvement exists, shall be released and discharged under the provisions of § 34-28-17, unless unreasonable conduct by the owner or lessee or tenant has contributed materially to the facts giving rise to the filing of the complaint.