Big purchases: cars, housing, and counting the cost

Where budgets actually break

Skipping lattes never rescued a budget that was wrong about the car and the rent. Housing and transportation are the two largest spending categories for most households, and they share a dangerous feature: you commit once, then the cost arrives every month for years, whether the month is good or bad. Small-purchase discipline can be corrected next week; a big-purchase mistake compounds for the life of the lease or the loan.

This is exactly the situation Jesus describes in Luke 14:28 (KJV above). The tower-builder’s failure is not building; it is committing before counting. The application to money is Jesus’ own illustration, and it lands hardest on the two biggest towers most of us ever build: what we drive and where we live.

Cars: the payment is not the price

A car costs far more than its payment. AAA’s annual Your Driving Costs study put average new-vehicle ownership at about $11,577 per year (roughly $965 a month) in its 2025 edition, counting depreciation, insurance, fuel, maintenance, finance charges, and fees. The largest single line is depreciation, the silent one: the value the car loses simply by aging, over $4,000 a year on an average new vehicle in that study.

So count the whole tower before you sign:

A reliable used car bought with cash or a short loan, driven for years, is the quiet path most budgets can actually carry. If a loan is involved, read big debts and co-signing first. The borrower-lender relationship in Proverbs 22:7 does not pause for good intentions.

Housing: the 30 percent line

The most widely used affordability standard comes from the U.S. Department of Housing and Urban Development: households paying more than 30 percent of income for housing are considered cost-burdened, likely to struggle affording food, transport, and medical care. It is a measuring line, not a law of nature. In expensive cities many people must exceed it for a season; some incomes allow comfort well above it. But every point above 30 percent is taken from giving, saving, and margin, and the house takes it first, every month.

Proverbs 24:27 gives the order of operations: establish the field (steady income, a funded emergency reserve, debts under control) and afterwards build the house. Renting while the field gets in order is not failure; it is the verse.

Before the signature, and again if a payment is already late, HUD-participating counseling agencies will walk through buying, renting, and default. HUD says foreclosure, eviction, and homeless counseling are always free; other counseling may carry a fee, which must be disclosed first and waived if you cannot pay. The number is (800) 569-4287, and the CFPB’s how to avoid foreclosure page points to the same line. The steps once the mortgage itself is behind are on getting out of debt.

The waiting rules

For wants that are not urgent, time is the cheapest counselor you can hire:

• The 24-hour rule: wait a full day before any non-essential purchase. This is folk wisdom, not science (no one owns it), but it works because desire manufactured by a moment fades in a day, while a real need is still there tomorrow.
• The 30-day rule for big-ticket wants: park the money, set a calendar reminder, and decide with a cool head. Proverbs 21:5 links haste to want and diligent planning to plenty; a month of waiting converts a hasty decision into a diligent one.
• For the biggest commitments (a car, a lease, a mortgage) add counsel. Plans are established by advisers (Proverbs 15:22, paraphrase), and a friend who has owned the thing you are about to buy will count costs you cannot see yet.

Sit down first. Count the whole tower. Then build what you can finish.

Try it yourself: open the interactive tool for this lesson.