Using the Multi Calendar you can adjust the pricing or minimum nights for selected dates.
Follow these steps:
Access the Multi Calendar module from the main menu.
Either click on the desired date or select a range of dates by dragging your cursor over the desired dates. This will open a pop-up menu
For pricing: Enter the desired amount in the "Price" field
For min night: Enter the number of minimum nights allowed in the "Min nights" field
Hit Save.