Like airfares, hotel prices can vary dramatically between sources—and from one day to the next. Aggregator websites such as kayak.com are a good place to start, but it pays to search third-party sites such as Expedia and hotels.com as well—they often run one-time deals you won’t find elsewhere. And don’t overlook the old-fashioned way, the telephone: a reservationist or travel agent may know of a non-Internet deal that you simply can’t refuse. T+L Test Case The …