Car finance, APR rates and per week in adverts; help understanding them
Easier to copy paste than type this out. Credit: www.financeformulas.net Note that the present value would be the initial loan amount, which is likely the sale price you noted minus a down payment.   The loan payment formula is used to calculate the payments on a loan.   The formula used to calculate loan payments is exactly the same as the   formula used to calculate payments on an ordinary annuity. A loan, by   definition, is an annuity, in that it consists of a series of future   periodic payments. The PV, or present value, portion of the loan payment formula uses the   original loan amount. The original loan amount is essentially the   present value of the future payments on the loan, much like the   present value of an annuity. It is important to keep the rate per period and number of periods   consistent with one another in the formula. If the loan payments are   made monthly, then the rate per period needs to be adjusted to the   monthly rate and the number of periods would be the number of months   on the loan. If payments are quarterly, the terms of the loan payment   formula would be adjusted accordingly. I like to let loan calculators do the heavy lifting for me. This particular calculator lets you choose a weekly pay back scheme. http://www.calculator.net/loan-calculator.html