In both cases, they provide the hotel with a module that integrates into their website. The only technical operation they need to perform is only the initial integration. Once it’s placed on the website, the reviews will automatically update.
HotelSearch is a free service available for the hotels that use their reservation system, although not exclusively. The look of the reviews can be customized to adapt it as much as possible to the style of the hotel’s website. Some examples of the official website of hotels that use the HotelSearch review system are: Moderno, Europa, Rívoli Ramblas, Carlos V or Pueblo Acantilado. To request the service HotelSearch, please, contact email@example.com.
As TripAdvisor does not have a reservation system it only feeds from the users that come from their own TripAdvisor website, and it doesn’t give the user the chance to write a review as does HotelSearch.
TripAdvisor’s reviews can be requested through http://www.tripadvisor.com/OwnerFeeds