If you are looking to cut down costs where possible, this is a great idea to follow up. In most scenarios, you will need more than the vehicle. For an instance, a GPS or a baby seat might be something you require. Car rental agencies will do a pretty good job at meeting your requests but with a catch. Yes, as with the previous point, they are likely to charge more than the usual rate for this. If you do want a GPS, try making use of the navigation apps on your phone as they can considerably bring down costs.