How much would you be willing to pay, per-night, for a room at a four- or five-star hotel in Seattle? How about $67? Does that seem fair?

What about a room in the four-star Hyatt Regency in the Chicago Loop? Do you think $58 per night is reasonable?

Would you rather be in Philadelphia? You can stay in the four-star Loews Hotel in Center City for $72 per night.

We know, we know, it seems too good to be true. But after several months of shopping hotel rates, we consistently found that we were able to secure rock-bottom hotel rates at four- and five-star hotels by simply spending some time patiently plugging away on Priceline’s site.

What is surprising is that the rates we were able to obtain through Priceline were so much lower than those available on other booking sites. For that Seattle stay, which we booked for $67 at the Edgewater Hotel, almost all other sites we checked quoted a rate of $216 per night at the same hotel; for the Chicago stay, rates at most sites for the Hyatt Regency were $189 per night; and for the Philadelphia stay, most other sites’ rates at the same hotel were $199 per night.

Furthermore, these low rates weren’t flukes: when pricing hotel rooms in several major U.S. cities for several different time periods, we were able to secure steeply discounted rates from Priceline just about every time we tried, including when we shopped for rooms the day before the trip and several weeks before the trip.

To put this in perspective, we should note that parking at that Chicago Loop location was $48 per night. If only you could get your car on the elevator, you could treat it to its own luxury room for just a few dollars more.

We searched for hotel rates using several scenarios in four major cities on popular online booking sites (Cheaptickets.com, Expedia, Hotels.com, Hotwire, Orbitz, and Travelocity); on the hotels’ own websites; and by phoning the hotels’ reservations desks. Time and again, the best rate we could find was by using Priceline. The table at the end of this article shows the full results.

Priceline’s website gives users two options for searching for hotel rates (and airline fares and car-rental rates). One option lets you use the site just as you would use Expedia or other online-booking sites—Priceline lets you search an area for a hotel and shows availability and rates for the dates you’ve selected. We’ve found that this option generally offers per-night rates that are about the same as at the other online-booking sites.

Priceline’s other option lets you “name your own price,” and it is by using this option that we found extraordinarily low rates. With this option, you enter the city where you will be traveling and the dates for which you will need a hotel room. You then enter the price you would like to pay and Priceline notifies you whether or not your price was accepted.

One major difference between Priceline’s name-your-own-price option and its standard search option—or the search options offered by most of the other sites—is that you don’t get to choose the hotels where you would like to stay; if your price is accepted, you are automatically booked at a hotel Priceline picks for you—and your credit card is charged for the hotel room—no backing out. Also, the name-your-own-price option doesn’t actually let you check rates for several hotels; if your price is accepted by any hotel that meets the conditions you set, that’s where you’ll be booked. Because of this lack of choice, Priceline bidding works best if you always bid only on four- or five-star hotels—so you can be reasonably sure of ending up at a nice place.

An obvious strategy would be to enter an extremely low rate—say, $20 per night—and then if that price isn’t accepted, simply continually add to your bid until it is accepted. But Priceline doesn’t allow this. If your bid is not accepted, you’ll have to wait at least 24 hours until you can rebid using a higher rate. And since Priceline tracks its users’ bids using not only their credit card numbers, but also the billing addresses associated with their credit cards, you can’t game the system by simply using a different credit card every time you bid.

But if your rate is not accepted by Priceline, the site does allow you to rebid a second time so long as you expand your search to additional areas in the metropolitan area where you will be staying or by adding a higher or lower category of hotels according to Priceline’s star-level rating system. It is this feature that you can exploit to try a low rate without having to wait 24 hours to rebid.

Below, we take you, step-by-step, through the system we used. Be aware that it might be confusing to try to follow each step unless you’re sitting at a computer, following along while using Priceline’s site. Also, don’t be too alarmed by the fact that our strategy involves 12 steps. Once you get the hang of Priceline’s site, you’ll find the process of submitting bids and then rebidding takes only a few minutes. Further, we found that we usually had to re-bid only two or three times in order to obtain a great price from Priceline.

1. Before turning to Priceline, start by checking rates and availability on Expedia, Travelocity, etc., for four- and five-star hotel rooms for the city and dates of your trip. Don’t bother checking more than a few sites—you’ll probably find little price variation among these sites. (As we explain below, in most cities our method works best for rates from four- and five-star hotels; but this shouldn’t trouble you, since the rate you’ll be able to get via Priceline for a high-end hotel is usually only $50 to $75 per night.) The reason to check these other sites is to make sure that you’re willing to stay in the hotel with the lowest rates for the star rating you select for the area and dates you’ll be staying, because when we conducted our shopping, we found that these were often the hotels where Priceline booked us. 2. Go to Priceline’s website, click on “Hotels,” and then click on “Bid Now.” Enter the metropolitan area where you will be traveling and the dates when you will be staying. 3. The site will now return a page showing you Priceline’s geographic zones for that city. For example, for Las Vegas, Priceline has 11 geographic zones: Boulder Strip, Convention Center, Fremont Street Area, Henderson, Las Vegas Airport, Las Vegas Strip North, Las Vegas Strip South, Nellis/Las Vegas Speedway, Summerlin, and West of Strip. 4. Select the first geographic zone listed and jot down whether or not that area has a four- or five-star hotel located there, according to the options that appear under the “star level” selection portion of the Web page. Then de-select the first zone, select the second zone, and note whether it has any four- or five-star hotel options. Do this for each of the zones Priceline lists for your destination city. 5. Decide on the geographic zone listed on Priceline where you would most like to stay. Note that in order for our strategy to work, your preferred zone has to be one for which Priceline lists a four- or five-star hotel option. De-select all other zones, select just your preferred zone, and in the hotel star-level section select the highest star-level option available. 6. Under the name-your-own-price section of the Web page, enter $50 per night. We found this to be about the lowest rate Priceline would accept. If, when checking Expedia, et. al., for rates, you found per-night rates below $100, you might consider starting your bid at $40 or so. On the other hand, if you found that the lowest rate available from those sites for a four- or five-star hotel was more than $300, you might want to consider starting your bid at a higher threshold (say, $70) so that you don’t waste too much time. But in our tests, we always started with $50, and most of the time were able to find a price between $50 and $70 per night, so a starting bid of $50 seems reasonable. 7. Enter your name, address, credit card information, etc., and have Priceline check to see if your bid was accepted (ignore all the ominous warnings that your bid is likely too low to be accepted). 8. If your bid is accepted, congratulations—you’re all set with a hotel room at a substantial discount. If your bid is not accepted, Priceline will now give you the opportunity to try again, so long as you select an additional geographic zone. This is the key to our strategy. Go ahead and select an additional zone, but add a zone that does not have a four-star hotel located within it (use your notes from Step 4). Doing this means you can increase your bid by $5 or so and have Priceline check its rates again without your being exposed to the danger of having to stay in an area you don’t prefer (since the second zone you’ll be adding doesn’t have any four- or five-star hotels) and without having to wait out Priceline’s 24-hour embargo on rebidding. 9. If Priceline does not accept your second bid, immediately close your browser window. Then start again at Priceline’s site. This time, select your preferred geographic zone and also a second geographic zone that does not have in it a four-star hotel—but make sure the second zone you select isn’t the same as the zone you added to your previous bid in Step 8. Up your bid by another $5 or so, enter your billing information again, and let ’er rip. 10. If your bid still isn’t accepted, you can select an additional geographic zone (just select the same secondary zone that you used in Step 8), increase your bid again, and resubmit it to Priceline. 11. Still no success? Close your browser and repeat until Priceline accepts your slightly inflated offer. Each time you start over, make sure to include a different, secondary geographic zone that does not have a top-tier hotel. 12. If you run out of secondary zones without top-tier hotels to include in your bid, just wait 24 hours and start the process all over, using a slightly higher bid than what you ended with the day before.

The only other site that offered rates that were anywhere close to Priceline’s was Hotwire, which operates under a principle similar to Priceline’s. With Hotwire, you search for a hotel room in a specific neighborhood with a certain star level and the site returns a per-night rate for a hotel that meets your search conditions. If you are willing to pay that rate, then you book through Hotwire’s site, but you won’t know the actual hotel that is offering that rate until you’ve booked (and your credit card has been charged).

There was one scenario we tested in which Priceline was not able to generate a lower rate than the other booking sites. When we tried our system to book a hotel room for the New Orleans Jazz & Heritage Festival—which is one of the largest gatherings in the U.S. each year—the lowest rate we found on the other online booking sites for a four- or five-star hotel room was $209 at Hotwire. We began our bidding process on Priceline at $60, and increased our bid by $3 or $4 before finally surrendering once we hit $245 without successfully getting Priceline to accept our bid. So, if you are planning travel to a place where the hotels are already almost completely booked—or expect to be—using Priceline might not provide you with a discounted rate. On the other hand, it’s still worth a shot.

Booking through Priceline does have some disadvantages.

First, when naming your own price, you can’t specify with Priceline the exact hotel where you’d like to stay. This may be a problem for you if you will be attending a conference or a meeting that will take place at the hotel or if you want to make sure you will be staying within a few blocks of the meeting, a specific tourist site, a sports arena, etc.

Another drawback: you might not agree with Priceline’s rating system for four- and five-star hotels. For example, Priceline considers Crowne Plaza properties to be either three- or four-star hotels. In our experience, that sometimes seems a bit generous. Since Priceline doesn’t allow you to exclude specific hotels from the bidding process, you might get stuck with a hotel for which a four-star rating is a stretch.

You might also want to avoid booking with Priceline—and other booking sites that require prepayment—if there’s a reasonable chance your trip will be cancelled. On the other hand, if you secure a rate at $57 per night via Priceline and you have to cancel your trip, you won’t be out much money if you are booking only for a short time.

One last drawback to using any booking site that requires you to prepay for the room is that by prepaying, you lose a great deal of leverage when dealing with the hotel management if things don’t go right. For example, if you’re assigned a room with a view of a parking garage instead of water views or if your assigned room is in a noisy area of the hotel, you’ll have to count on the benevolence of hotel staff to make things right, since you’ve already paid for the room.

A final caveat: be sure to keep in mind that although these price-saving strategies should provide you with per-night rates that are competitive with what you pay to live in your home, you'll still have to pay the hotels' very expensive rates for all other services-like the $48 per night to park at the Hyatt Regency Chicago. And, unfortunately, Priceline has not yet built a name-your-own-price component for in-hotel meals and mini-bar drinks.