Buying a car or truck can be one of the biggest purchases you'll ever make, so getting the best deal you can is extremely important to keep your finances healthy. But with the challenges of haggling on price, trade-in value, and financing, it can be hard to know how much your budget can handle.

In the following video, Motley Fool investment-planning editor Lauren Kuczala talks with longtime Fool contributor and personal finance expert Dan Caplinger about how to plan for a new car purchase. Dan points out that the key first step is to figure out how much you can afford, considering all the expenses of vehicle ownership. Then, use the incentives and financing options that major car companies offer to their fullest, considering not just monthly payments but also total costs over the the lifespan of your vehicle. Dan and Lauren also discuss the pros and cons of buying new or used cars in the current market.