“[U]nless public policy is affronted, parties to a civil dispute are free to chart their own litigation course and, in fashioning the basis upon which a particular controversy will be resolved, they ‘ “may stipulate away statutory, and even constitutional rights” ’ ” (id., quoting Mitchell v New York Hosp., 61 NY2d 208, 214 [1984]). Tenants’ contention that the stipulation is void because it purported to modify the statutory warranty of habitability by requiring written notice, raised for the first time five years after they received the benefits of the stipulation, is unavailing. Tenants’ arguments overlook the fact that the stipulation was the culmination of extensive arm’s length negotiations to settle the latest of many disputes arising out of the failure of tenants — one of whom is an experienced real estate and landlord-tenant attorney — to timely pay maintenance based on dubious habitability claims.