Many subprime lenders are willing to approve car loans for individuals with poor credit, provided that the loan amount doesn't exceed a 110% Loan-to-Value (LTV) ratio. This ratio is calculated using the invoice price for new cars and the average trade-in value for used vehicles. As a general guideline for people with poor credit, it's advisable to have enough cash on hand to cover the Tax, Title, and License fees, which typically add up to around 10% to 15% of the total sales price. However, it's worth noting that down payment requirements may increase if you have a trade-in with negative equity.