In order to get a good overview of your objects and their coverage with agreements in the past and in the future open up Units > Timesheet.
The timesheet view gives you an overview of which units are covered with active rental agreements and which ones are currently vacant.
You can select the period you are interested in and choose whether to display the data in days, weeks, or months.
Agreements are distinguished by colors depending on whether they are active, about to end, or already ended.
You can also filter out the objects based on the object type.
Once you click on the corresponding agreement it opens up the detail view.