## Calendar math
List every installment due date on one month view with rent and utilities. If two BNPL hits land the same week as rent, you created a synthetic payday loan. Price the plan with BNPL true cost & APR calculator.
## One in, one out
Do not open a new plan until the last installment of the previous one clears. If balances blur, consolidate deliberately via Debt consolidation savings calculator or attack with Credit card payoff logic — not with another promo.
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