Let's say someone purchased an item on an instalment payment plan from a company. They also subscribed to their services. The instalment scheme is separated from the monthly service fee. That means every month they pay for the service fee and the instalment for the item separately.
For e.g, the item costs $5000 with a monthly payment plan of $500. The service fee is $25 per month and is a pay-as-you-go service. The terms are that the customer can switch service providers anytime. They can use the item elsewhere too. There is no vendor lock-in.
Assume, for some reason, the company dropped the installment scheme and offered to have the balanced amount included as the monthly service fee instead. The customer can continue to make the monthly payment as usual but as a service fee.
It seems unaffected on the surface but I reckon service and the instalment payment plans are two independent contract terms.
What is the downside/upside to the customer accepting this offer to change the terms?
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Thank you for editing my post and rephrased the question with more clarity.
I understand it depends on the actual contract terms. I asked the question on the assumption that contracts have to work within stipulated guidelines to be valid. And based on the nature of the contracts, what are the tradeoffs one should be concerned with?