Porsche 718 Boxster S vs Porsche 718 Cayman GTS 4.0 — Cost of OwnershipCompare any two cars on the true 5–10 year cost of ownership: purchase price, fuel or electricity, insurance, maintenance, registration, depreciation and resale value. EV vs gas, lease vs buy, with every assumption editable.Porsche 718 Boxster S: $124,241 net over 10 years ($6,004/yr running). Porsche 718 Cayman GTS 4.0: $140,519 net over 10 years ($6,456/yr running). Estimates for Cedar Park, TX; every assumption is editable.