Availability calendar for K2

I need to turn K2 in to a booking application. Every K2 item must have an availability calendar and must be shown in search results if vacant dates are entered in search. That brings us to the search module.. Parameters for search are calendar dates and number of persons that are renting the apartment, in example "apartment for three people from 14.07.2013. - 23.07.2013", so there should be a drop-down list for selecting the number of people, and two empty fields for dates, but when you click in the first field to enter the date a calendar should pop-out and let you select the date by clicking it. Also, there should be a possibility to show the price for the selected dates in search results and on item page (prices of apartments vary depending on the selected dates).