> repair them for X money
Plus (X / 1.5) * (1 - S), where S is probability of successful repair.
Plus the repair cost of the next thing to go if many parts are reaching the end of the design life (= warranty * 1.1)
Plus the cost of your time either repairing it yourself or finding someone to repair it.
Plus the cost of your time either repairing it yourself or finding someone to repair it.