Work out layaway payments and total cost with fees.
Layaway spreads a purchase over instalments without interest, but not without cost. The deposit comes off the price first, the balance divides evenly across the instalments, and the fees — a set-up charge plus a small charge on each payment — are what the plan actually costs you. Expressing those fees as a share of the price is the honest comparison, because a 15 set-up fee plus 1.50 per payment on a 640 item is over two and a half percent, charged on money you have not yet borrowed.
Instalment
Each payment = (price - deposit) / number of instalments + per-payment fee
Cost of the plan
Total fees = set-up fee + per-payment fee x instalments; total paid = price + total fees
You do not get the item until it is paid off, which is why there is no interest and no credit check. The trade-off is waiting, and the risk that cancellation forfeits part of what you have paid.
Policies vary and often retain the set-up fee plus a restocking charge, with the rest refunded. Ask for the cancellation terms in writing before the first payment — that is where the real cost of the plan sits.