u/Experiencetheoutdoor

What does everyone do when a customer breaks a contract on payments? My contract states 20% down payment, 40% once the ceiling is installed then the remaining 40% once the trim and finish work is done. The ceiling has been installed for over a month now with no payment for it and the customer keeps saying it’s not done because the trim isn’t finished on it and keeps saying I don’t care what the contract says I’m not paying until it’s done.