Earlier purchases are already paid: compare what your child must pay from now
By Erik Nilsen · Kroni3 min read
When your child has already bought parts of something, a new bundle can make the old price frustrating. Money already spent does not automatically come back. Separate the total spent across the whole history from the cost of the decision facing you now.
Calculate two routes forward
In a hypothetical example, your child bought four particular cards for 40 units altogether. They want two more to make six. The two missing cards cost 20 together. A complete pack of the same six costs 45. Your child has 30 remaining, and the old cards cannot be treated as sold or refunded in this exercise. All prices are arbitrary teaching numbers.
Buying the two missing cards requires 20 units now and leaves 10. The complete history costs 40 + 20 = 60. Buying the complete pack requires 45 now, or 15 more than your child has. The complete history would then cost 40 + 45 = 85, with four extra cards already owned.
It is true that starting from nothing, a complete pack for 45 would cost less than 60. You are not starting from nothing now, though. The earlier 40 cannot be deducted from the payment for the new pack.
Treat the history as information, not new money
A realistic snag is your child saying “the pack saves 15” by comparing 45 with 60. Show the column labelled “pay from now”: 20 versus 45. For the same target of six cards, the pack requires 25 more of today's money than the missing pair.
If your child has a concrete use for the four extras, consider their value separately. Do not assign a guaranteed resale price without an actual agreement. A possible sale cannot pay for today's order.
Keeping the original four and waiting is another option. Earlier purchases do not make completion compulsory. Your child need not spend another 20 to make the first 40 “worth it” if their wish has changed.
When starting another collection later, use the experience to compare individual purchases and a pack beforehand. For today's decision, ask your family: “What do we already have, and what new payment does each route forward require?”
Carry the calculation into your family agreement
Kroni can keep track of your child's virtual balance. The app does not transfer money, so any actual purchase is paid for outside it. Agree on what you will record, then check the amount with your child afterwards. Do not deduct a possible cost as though the purchase had already happened. Read about allowance in Kroni.
