Google has been testing a program "Hotel Price Ads" that shows ads for hotel searches inside of Google Maps.
It looks like those ads are headed to Google's main search results soon. As the three new types of hotel price ads, all of which are showing up outside of Google Maps on local searches done on Google.com.
Hotel Price Ads: Three New Google.com Formats
In this example, five of the seven hotel listings have the hotel price ads attached. Just like the test inside Google Maps, clicking the price shows a dropdown with prices from advertisers participating in the program by giving Google their pricing information.
Two other examples in Google.com search results: first, hotel price ads in the Google Places results, and then a screenshot of the ads on a local inbox result for a single hotel.
A Google spokesperson confirms that this is an experiment. "We do not have any further to add at this time about future plans, but do want to reiterate that these ads for hotel prices do not change the organic ranking of the affiliated properties, be it in Maps or elsewhere."