What car can your income actually carry?

Three well-known rules answer what car you can afford, and they disagree by hundreds of thousands of rand. This runs all three at once, with fuel, insurance and upkeep counted in.

The three, as applied here. A payment cap keeps the instalment under 15% of take-home pay for a new car, 10% for a used one, with the whole transport bill under 20%. The 20/4/10 rule wants 20% down, a term of 48 months at most, and all car costs under 10% of gross income. The 1/10th rule caps the cash price at a tenth of a year's gross. That one is a wealth-builder benchmark, stricter than most South African buyers use.

Start from your income to see the price each rule allows, or from a car's price to see the income each rule expects.

Running costs are counted in every answer. Fuel, insurance and upkeep can rival the instalment. Enter them once on the shared Running costs card and every Auto tool uses them.

Bring your take-home pay and your gross pay, because the payment cap works on take-home while 20/4/10 and the 1/10th rule are written against gross. Then the finance: new or used, the term, your deposit, any balloon, and a rate. Pick your credit band and a realistic rate fills itself in.

The result gives your rule's answer as the headline, all three side by side in a chart, and a transport-share card grading the instalment plus running costs against the 20% all-in ceiling.

These are guidance rules. A lender runs its own credit test. The bond affordability tool runs the legal NCA test on a home loan; the finance and balloon tool prices an exact car deal.

Money Cat is an information tool, not financial advice. Confirm any figure that matters with your bank, lender or a registered professional.