Abstract
<title>Abstract</title> <p>Product-as-a-Service (PaaS) with retained ownership is one of the most direct routes to remanufacturing at scale, because the provider recovers its products as cores at the end of every use cycle. Whether this is financially viable, however, remains the binding question: most manufacturer-run car-subscription programmes have been withdrawn citing insufficient viability. This paper adapts a validated life-cycle-costing model, developed for a construction-machine manufacturer, to passenger internal-combustion cars and applies it to a real operating programme (Toyota/KINTO) parameterised entirely from public data. The model compares a one-off sales model with a retained-ownership, remanufacturing-based PaaS model through the provider's net present value and the user's total cost of ownership over multiple use cycles. At base case, subscription is cheaper for the user but unprofitable for the provider: the fee the provider requires exceeds the fee the user accepts by about EUR 75 per month. Robustness analysis shows this gap is provably invariant to the maintenance, repair and insurance estimates and is governed by two parameters, manufacturing cost and used-vehicle residual value, with a win-win emerging only below roughly 47% three-year value retention or through design-led reductions in manufacturing, remanufacturing and fleet-management cost. The results quantify why car subscription retreated and identify the design-for-remanufacture conditions that would make it viable.</p>