In a typical "lowest rate" hotel promotion, the site guarantees it will have the same low room rates that are available through participating hotel chains' Web sites and toll-free numbers, which will be the lowest rates publicly available to consumers on the Internet. If you find a rate lower than the best available rate offered by the site that is bookable on an unrelated Web site for the same hotel, same room type, same number of guests, same currency and same dates, and advise the site within 24 hours after booking your room, the site says it will cover the first night of your stay free, refund twice the difference or some such.

Where's the wiggle room in that promise? Mainly in the condition that the competitive rate be "publicly available to consumers on the Internet." In further explanation, the fine print excludes: special rates available only to members of membership organizations and limited demographic groups. Translation: The guarantee does not apply if the lower rate you find is for seniors or members of AAA, AARP or a similar organization. Add to that group rates, corporate rates, wholesale rates or affinity/association rates. Translation: Negotiated discount rates on sites such as Expedia do not qualify for the guarantee. Rates for which you don't know the name of the hotel until you make a nonrefundable booking don't count either. Translation: The guarantee does not apply to Hotwire or Priceline prices.

Clearly, your chances are pretty slim of finding a lower room rate that gets through all of those exclusions. And that's the whole idea.

Get the full story at the San Francisco Chronicle