But the opportunity cost is also $10 a month for however many months the plan runs. It would be appropriate to think of other monthly payments with the same opp

But the opportunity cost is also $10 a month for however many months the plan runs. It would be appropriate to think of other monthly payments with the same opportunity cost (like a Netflix subscription), but it would be inappropriate to talk about things that cost $400 up front without also recognizing that you wouldn’t get those things until the end of the payment period.