It's wrong to think that the majority of service costs as vehicles age is in the engine and oil changes. Most new cars engines/tranmsmissions will go very larg

It's wrong to think that the majority of service costs as vehicles age is in the engine and oil changes. Most new cars engines/tranmsmissions will go very large distances with no mechanical failure if serviced properly. Exceptions exist, but for the most part, engines are durable and have minimal service requirements. Cars must have suspension replacements, plus fixed for lots of little car systems that can start failing with age. An example is windscreen washer systems. Usually required for safety inspections, they can stop working, and it's expensive to remove and replace them because they wind their way around multiple components. Same for hvac systems and lighting systems and on it goes. I bring this up because the worth of a tesla will not just hinge on the ability to fit a new battery pack and go. It will also hinge of the ability of the basic vehicle and non-propulsion systems to continue to work and become economically serviceable. Most cars can get a substantial mechanical refresh for the current cost of a new tesla battery - but this is not usually done because the car itself develops many other failings and a new one is faster and easier to purchase. So the resale value will swing on not only the battery replacement cost, but may other things besides. Only then will we know what the used value looks like.