Walker, a single parent employed full-time, lived with their two young children in an apartment until it was slated for demolition by a real estate developer. Shaw, a college student who inherited a mortgaged house on Burgundy Ave and struggled with living expenses, offered temporary accommodation to Walker. The arrangement worked well, leading to a permanent living agreement where Walker shared household expenses and contributed half of the mortgage payments over three years, as well as paying $5000 for a bathroom addition, which increased the house's value by $3000. After Shaw graduated, found employment, and got engaged, tensions rose, and Walker moved out, seeking reimbursement for the home improvement by requesting the court to impose an equitable lien on Shaw's property. What result