Stay near a subway stop. When choosing a hotel, the proximity of a subway (Métro) stop is perhaps more important than even the quality of the rooms. Why? Paris is made for exploring on foot. Be sure to pick a hotel that's less than 10 minutes' walk to a Métro stop. The right bank arrondissements numbered 9-12 have excellent access to the Métro—plus, some of the city's best value restaurants. Fifteen minutes on the subway might save you $50 per night in hotel costs. Look for hotels that are near subway lines 1, 7, 8, and 9—these routes have stops near the major monuments.
Avoid hotels in the city center. Paris is split into numbered districts, or arrondissements. The ones with the lowest numbers are nearest the center of town, such as the 5th (a.k.a. the Latin Quarter, which borders the Seine River and is home to the Sorbonne and tons of students, bookstores, and boutiques) and the 7th (where you'll find the Eiffel Tower and the Musée d'Orsay). But there are wonders to behold throughout Paris, such as in the 14th (frequented in the 1920s by Ernest Hemingway, Gertrude Stein, and other members of the expatriate "Lost Generation," and still a haven for literary types) or the 18th (the old stomping grounds of artists such as Pierre-Auguste Renoir, Henri Matisse, and Henri Toulouse-Lautrec at Montmartre, as well as one of Paris's best flea markets, plus the famed Basilique du Sacré-Coeur). As a rule of thumb, the farther you are from the center of town, the better the rates for hotels.
Watch out for breakfast charges. With rare exceptions, all taxes and service charges are included in room prices in Paris. Breakfast, on the other hand, often costs extra—from $7 to upwards of $40 per person. If you don't want breakfast, be sure the hotel knows that at check-in, and verify at checkout that you haven't been charged.
Keep your eye out for "double" trouble. A single room is obviously equipped with one bed for a single person. But there's often some confusion between double and twin rooms. A double is supposed to contain one bed large enough to sleep a pair of guests, while a twin room should have two single beds. But be aware that the particulars may get lost in translation. Always ask specifically what sort of bed(s) your room contains—both when you reserve and when you check in.
April in Paris may not live up to its romantic reputation. Frank Sinatra crooned about its glories, but April in Paris is often wet and dreary. For brilliantly crisp weather and manageable crowds, June and September are probably your best bets. Meanwhile, July and August are the busiest and generally most expensive months for tourists. As for the off-season (winter), most hotels lower rates and airfare is cheapest—but you might wind up spending a lot of your time indoors. The damp days of midwinter are known to chill visitors to the bone. Luckily, many of the capital city's pleasures can be found inside, in its galleries and cafés.
Hotels with old-world charm may have old-school reservation systems. Independently owned properties are often terrific values—but they often do not allow guests to reserve rooms instantaneously online. Perhaps their owners feel that such a booking technique is too impersonal. In any event, you may have use e-mail or the phone to book a room.
Look to the stars. The French government rates each of the 1,500 or so hotels in Paris on a scale from one to four stars. One-star properties—where double rooms can be had for under about $75 per night—are sometimes quite charming, with courtyard gardens, for instance. Other one-star hotels are downright seedy, with rooms that are tiny, unkempt, and bathroom-less. With each additional star, the likelihood increases that a hotel has additional amenities, such as an elevator, free Wi-Fi, or a concierge. The moral is: The rating system provides a rough estimation of quality, but it's far from perfect. You'll generally find the star rating listed on the hotel's website. (Can't find it? Contact the hotel.) Note that the official stars won't necessarily align, so to speak, with guidebook and hotel-booking-site ratings, which use different criteria.
For longer stays, consider an apartment instead of a hotel. Short-term rentals are best if you're staying a week or more. There are two types of Web resources for short-term apartments. The first type will help you find luxury digs that are more spacious than the typical Parisian hotel, but cost about the same, giving you a bigger bang for your euro. A swank apartment on the Ile-Saint-Louis, for example, sleeps four for 190€ ($240) per night. That works out to about $120 per couple per night for a 17th-century address overlooking the Seine. Guest Apartment Services is a good site for these high-end rentals. A second type of website lists rentals on the other end of the scale. For example, websites like Venere offer smaller, typically IKEA-furnished rentals from 100€ ($126) per night. Both Guest Apartment Services and Venere accept online reservations and deposit by credit card. Note, though, that many smaller companies accept deposit only by bank transfer. (See this list of companies.) Always read the reservations policies carefully with an eye out for traps, such as the policy on cancellations. Be particularly wary of negotiating any rental found on a message board like Craigslist. Deposits have been stolen via short-term rental scams made through such sites. For full advice on how to arrange a vacation rental, see our Vacation Rental Handbook.