More often than not, a person will base his or her entire decision on the price. This is especially true when one is on-line creating their own itinerary without the help of a travel agent or trained professional, something that within 5 years from now will be standard practice. While price is undoubtedly one of the most important things to consider when making a reservation, it is not the first priority. The first priority should be to determine what kind of car you will need, based on a few different factors.
To begin, you must know how many people will be accompanying you on this trip. Remember that the European equivalent of a rental category will be smaller than its US counterpart, so make sure that you take notice of the model that they are quoting you for, along with the supposed size. Once you know what the model is, look it up on the internet and make sure that it will work for you. Some companies will quote you for what they bill as an intermediate car when it is in reality a compact size. Usually for 1 or 2 people, an economy will suffice, provided you have one suitcase apiece. In the event that you have more luggage than this, you may opt to put it in the back seat or upgrade to a larger vehicle. Keep in mind that if you are planning on stopping at any places where your luggage will be visible from outside the car, it is best not to keep it in the back seat.
For 3 people, a compact should be suitable. Sometimes, if you do not mind being a bit cramped on shorter trips, this will also accommodate 4 people. You may have to put some luggage in between the people in the back though. A car this size should be roughly the equivalent of a Ford Focus or Toyota Corolla here stateside. If you can afford it, I would definitely recommend an intermediate 4-door vehicle for 4 people.
For anything above 4 people, it is best to get a van, or more than one car. Once again, if you don