Opportunity cost the value of the best alternative you give up when you choose. Where it's taught Opportunity Cost & Trade-OffsBuy Now, Pay Later — or Save Up First? The True Cost of Financing a PurchaseBorrowing From Your Own 401(k): The Loan That Sounds FreeYou Just Got a Windfall: Where Should It Go?Rent vs Buy: It's a Break-Even, Not a Battle Try it with a calculator Opportunity Cost CalculatorFinance Vs Save Calculator401k Loan CalculatorWindfall CalculatorRent Vs Buy Calculator Appears in 7 other lessons Present Value: Should You Take the Lump Sum or the Payments?Which Dollar Is Worth Most: A Raise, a Side Hustle, or Cutting Costs?The Emergency FundThe Latte Factor: What a Small Daily Habit Really CostsCredit Cards & the Minimum-Payment TrapPaying for College: 529 Savings vs the Cost of Student DebtBuying a Car: New vs Used vs Lease Related terms APR (annual percentage rate)BNPL (Buy Now, Pay Later)Break-even (years to break even)Building equityCash discount / surchargeClosing costsDeemed distributionDeferred interest