The undercover shoppers at Delaware Valley Consumers’ Checkbook did nearly 2,000 searches for hotel-room rates and found that most travel-booking sites and hotel websites serve up the same prices.

Want a hotel bargain? It will require effort.

Although dozens of travel-booking websites seem to fight one another for our travel dollars, there is scant price competition for hotel bookings. Agoda, Booking.com, Expedia, Hotels.com, Hotwire, Kayak, Momondo, Orbitz, Priceline, Travelocity, Trivago, and many others are owned by travel giants Expedia Inc. or Booking Holdings, which together dominate the third-party online hotel-booking business.

Hotels have agreements with Expedia, Booking, and other travel sites that require all sellers (hotels included) to offer each room at the same price across all booking platforms. Before these price competition-killing requirements, you could get a range of rates either by calling the hotel itself, trying the hotel company’s toll-free line, or hitting the internet and comparing offers from several sites. Not anymore: Most websites Checkbook shopped spit out the same rates for the same stays.

Besides eliminating travelers’ opportunities to save by shopping around, hotels and third-party booking websites continue to gouge customers with hidden fees. The per-night rates shown in search results are rarely what you’ll actually pay.

The good news? There are some ways to save money — and avoid trouble — when booking hotel rooms.

Despite mostly finding the same hotel room prices across most platforms, shopping around sometimes scored surprising deals. For example, for a three-night stay at the Wyndham Grand Orlando Resort Bonnet Creek, the best total price (including fees and taxes) for a refundable rate on the hotel’s website for a “1 King Bed” room was $1,137. Most other major websites offered it for $936, but it was available at Booking.com for only $739 and even less — only $508 — for prepaid nonrefundable rate.

By not restricting yourself to a specific hotel or chain, you can usually save significantly. Compare costs among properties that offer roughly the same amenities. Besides being flexible on hotel selection, consider alternative destinations and dates. Checkbook’s shoppers found they often could save significantly by shifting their travel dates by a few days or weeks.

While the agreements between hotels and travel-booking websites don’t allow advertising different prices for the same room and dates, companies are permitted to offer lower rates if they restrict access to certain groups. For example, members of AAA or AARP might qualify for small discounts, and if you sign up for emails or membership with a hotel chain or booking website, you may be able to “unlock” lower prices.

Some companies circumvent hotel-pricing restrictions with “mystery deals,” such as Hotwire’s “Hot Rate” specials and Priceline’s “Express Deals.” When these rates were available, these two booking options consistently provided Checkbook’s shoppers with the lowest prices: On average, they saved about 28% compared to the prevailing refundable rates offered elsewhere, and mystery deals were about 20% less expensive than other nonrefundable options. In some cases, mystery deals offered prices that were half those found at most other booking sites.

Hotwire’s and Priceline’s mystery deals are a slight gamble. While they do display hotels’ neighborhoods, star levels, average guest ratings, amenities, and other features, they don’t provide properties’ names and exact addresses until after you’ve paid — no backing out.

It sounds risky, but you get plenty of info and filters to ensure you land at a good spot. By matching the number of guest ratings and property features with other listings of non-mystery rates in search results, about 90% of the time you can figure out which mystery deal belongs to which specific hotel.

Hotels and travel-booking websites are increasingly offering special rates to people who join their frequent traveler clubs, supply email addresses, connect via Facebook, or take similar actions. Joining up and logging in typically saved Checkbook’s researchers about 8% to 12%.

Most hotels now offer lower rates if you pay up front for a nonrefundable booking, and third-party booking sites do the same. Opting for nonrefundable rates saved an average of about 12% over refundable rates.

Hotels and booking websites usually list (5% or so) discounts for older adults, military service, teachers, and AAA or AARP members on their websites, if they’re available.

Companies such as Rakuten, BeFrugal, Mr. Rebates, and others help consumers score cash rebates for all kinds of purchases. These websites work with companies that pay commissions when they send them business. The sites then share a portion of those proceeds with customers. Cash-back companies work with most third-party travel booking sites and many hotel chains. Typical rebates are 3% to 8%.

Because booking websites and hotels mostly offer the same rates for specific stays, consider reserving directly with the hotel company, which might provide better room selection, free upgrades, bonus rewards points, or other perks. It’s also the best way to avoid a last-minute reservation cancellation due to overbooking.

Members can log on to Costcotravel.com for discounted hotel rates; on average, Costco saved about 6% off prevailing rates for sample stays. Not bad, but there weren’t many hotel choices — of 75 sample stays, only 13 were available to book through Costco.

Hotel booking websites often issue warnings like “Only two rooms left!” or “19 other travelers are looking at this deal!” For a previous study, Checkbook’s researchers spent several weeks searching eight major hotel booking websites and found all used such high-pressure sales tactics. The investigation found there’s usually still plenty of room left at the inns.

Hotel room prices tend to get less expensive the longer you wait to book.

Don’t pass up a great deal just because it doesn’t include staying with your preferred hotel brand for accumulating points. Hotel chains continue to cheapen their rewards programs. Don’t give up $500 in savings by booking with a different hotel due to fretting over lost points.

Especially if you can cancel or change flights, lodging, or car rentals without penalty, keep an eye on rates, and rebook if they plunge.

The policies pushed by hotels and travel-booking sites are usually bad buys. Wade into the fine print and you’ll find these policies provide thin coverage and have numerous exclusions. Another sign these policies aren’t worth much: Some credit cards offer customers similar coverage for free.

Delaware Valley Consumers’ Checkbook magazine and Checkbook.org is a nonprofit organization with a mission to help consumers get the best service and lowest prices. We are supported by consumers and take no money from the service providers we evaluate. Through special arrangement, Inquirer readers can access all of Checkbook’s ratings and advice free through Dec. 5 via Checkbook.org/Inquirer/Hotels.