I know little about the business of high-tech digital gear, but I can guess GPS makers such as Garmin and Tom-Tom are having a rough go. Increasingly, people use smartphones for guidance when on the move. For example, I no longer rely on my car's factory-installed GPS. iPhone's Google Maps app is easier to program, has much better maps, better guidance, and the destination can be changed by my wife while I'm driving (our car has to be stopped in order to request a new destination on the built-in GPS).

Depending on what it will cost for data while traveling in Europe, you might want to rely on your smartphone's Google Maps app. Another option is to buy a cheap, used GPS.

Whatever you decide, you will want to think long and hard about renting a GPS from a car rental company. They are expensive and don't always work. Rental fees range in price from about €5 to €21 per day. Some max out at €90 to €200 for a longer rental. And what you get isn't always the greatest. Rental devices are heavily used and we hear complaints they sometimes don't work properly. Most are multilingual but many renters find they are unable to set them to speak English. To rent a car whose price includes GPS, you will probably have to book more expensive fullsize or higher category cars. Few economy, compact or intermediate cars come with built-in GPS, and seldom is the price include in the overall rate.

The only problem with using Google Maps on a smartphone in Europe is the cost of international roaming. However, you can probably purchase an overseas data plan that will allow you to operate Google Maps while driving (prior to a recent European trip I paid AT&T $59 for a 300MB overseas data plan which, by being judicious, I didn't use half of).

However, even if you disable data roaming entirely, you can still use Google Maps in a limited way. Before starting out on an auto trip, connect the phone to the Internet via WiFi at your hotel or a café. Next, set your departure and destination points and Google Maps will create the route. Once you are in your rental car, even though Google Maps won't have access to the Internet, it will continue to show your position along the route by using satellites and cell towers. It won't provide verbal directions and you can't change the route, but it will keep track of your progress.

Another alternative is buy a used portable GPS. Right now on eBay, you can purchase used devices that include Europe maps for as low as $40. A Garmin Nuvi 670 with Europe and North American maps, which a few years ago sold new for over $600 (I know, I bought one) has a bid price of $49.99 and 'buy now' price of $99.95. My Garmin 670 still works great but it sits in a drawer; Google maps on the iPhone is better and a lot handier.

Beware. Some online travel sellers, notably Priceline's Rentalcars.com, are passing off intermediate-size MPVs (multipurpose vehicles) as fullsize seven-passenger vans. Such cars as the VW Touran, Opel Zafira, Ford Grand C-Max, and Nissan Qashqai can accommodate no more than five persons, and if all are adults, even five is a bit of a stretch. Most rental car companies put them in a category they term Intermediate Special or Intermediate Van.

Technically, it may be possible to squeeze seven people into some of these vehicles but they are definitely not the traditional, seven-passenger family van most customers have in mind when the are shopping for a rental car to carry six or seven persons when vacationing in Europe. The Nissan Qashqai, for example, is slightly smaller than the Toyota Rav4. In one example of blatant misrepresentation, the Greece-based online seller, Economycarrentals.com calls the Qashqai a seven-passenger minibus. In actual practice, this vehicle would be cramped with four passengers and luggage.

Nissan Qashqai: 7 Passengers?

These MPV vehicles are sold by new car dealers in both a five-passenger and seven-passenger configuration. In the seven-passenger setup, virtually all the luggage space is occupied by two folding "jump seats" that are only suitable for kids on short trips. Reputable rental car companies show them as being suitable for no more than five passengers. Be assured such vehicles will NOT handle six or seven passengers with luggage.

If yours is a party of six or seven, you need a Fullsize Van (FVMR, FVAR for automatics) such as the VW Sharan, Ford Galaxy, Renault Espace, Fiat Alhambra and a few others. Regrettably, some companies use the FDMR/FDAR designator for MPVs, and a few companies simply promise a seven-passenger vehicle without showing a typical make and model. When an example is provided, however, look it up in Google. A good source for vehicle information is Wikipedia which has descriptions and specifications for most cars. In online write-ups, words and phrases such as "compact," "intermediate," "5-7 passenger," “5+2” and "MPV" all indicate something less than a fullsize van.

A step-up from the fullsize FVMR is the eight or nine-passenger Standard Van (SVMR) such as the Renault Traffic, VW Multivan, and the Mercedes Vito.

Here's more to guide you in selecting the right rental car.

Get a quote on European rental car.

Before reading this you may want to refer to a comment posted by one of our rental car customers on TripAdvisor.

I hesitate to respond to this sort of thing, but we get referrals from the TripAdvisor forums and what is said about us there is very important. Here's our side of the story.

Ms. XYZ (of course we won't use her real name...or even the login ID she used at TripAdvisor) was indeed charged 74.75 plus 19% value added tax (not quite the $150 she claims) by the rental car supplier when she failed to return her rental car with a full fuel tank. Very high fuel charges are standard procedure with all rental companies in Europe. The voucher she received prior to her rental contained this language: "Client is advised to return the vehicle with a full fuel tank and to retain all gas receipts." Furthermore, all our customers are sent a link to our free special report entitled: "What You Should Know About Renting a Car in Europe" which contains this information: "If the rental company has to fill the fuel tank when you return the car, you'll pay as much as $18 per gallon, and perhaps a refueling charge as well. Bring back a near-empty tank and you might pay more than $200 for fuel plus a refueling charge." Since Ms. XYZ was unable to produce any receipts for fuel, or in any way document that the tank was not full at the start of the rental, we were unable to obtain a refund for her.

As to our inadequate service, Ms. XYZ does not mention the exchange of two to three dozen emails—between Gemut.com and herself, between Gemut.com and Auto Europe, and between Auto Europe and the car rental company in Europe—regarding the fuel charge and other issues related to her rental. Nor does she acknowledge in her TripAdvisor posts that through Gemut.com's efforts and the efforts of our partners at Auto Europe, the rental car supplier in Europe refunded 35.28 euros (about $45 at the time). The supplier incorrectly charged Ms. XYZ an additional day's rental which we were able to have refunded. We wonder if she understands that had she booked directly with the supplier, she would have been alone in seeking her refund from a car rental company whose offices are in Europe.

With respect to the dirty car, we are always disappointed when our suppliers fail to provide top quality service to our customers. I should again point out that our "What You Should Know About Renting a Car in Europe" report contains the following language: "If the car is dirty inside or out, refuse it," and "Don't leave rental location until satisfied." In addition, in the event of service problems with the supplier, each customer is advised to call the 24/7 toll-free-from-Europe help line.

To summarize, Ms. XYZ accepted a dirty car and one with a fuel tank that was not full. Both these scenarios are specifically covered in our “What You Should Know...” report, the link to which was emailed to her with the rental voucher before she left the U.S.

After her return from Europe, we assisted her in the same the way we do with all customers who encounter problems with a supplier; we collected the relevant documents, listened to her account of what happened at the rental counter, and then presented it all to our contact at Auto Europe who in turn forwarded it to the rental company in Europe. Ms. XYZ was unhappy with the outcome.

A final note: Ms. XYZ says she was injured prior to picking up the car. We fully understand her pain could have distracted her and her husband from challenging the rental car supplier in the ways we recommend. But unfortunately, when all is said and done, what we are left with is the paperwork...or lack of it.

If you are a Gemut.com car rental customer and have had a different experience with us, perhaps you would like to respond to her post at TripAdvisor. You can do so here.

Today, Sunday, January 27, if you book a compact car (4-door, VW Golf or similar) for one week, June 6-13, from the Frankfurt Airport, the prices you will pay at the websites of the major rental car suppliers, including 19% value added tax and 20% airport tax, are as follows:

• Avis: $307
• Europcar: $255
• Hertz: $282
• Sixt: $304

However, if you booked through Gemut.com...in addition to our personal service, expertise and guidance, pre- and post-rental support, a 24/7 toll-free-from-Europe safety-net help-line staffed by live humans...your price would be:

• $245 (the supplier is Europcar)

Get a written quote here or phone 800-521-6722.