The client records belong to both you and the client, not to Quenza B.V.
When you decide to stop working with Quenza, you can export any and all client records as a PDF and so can your clients.
You can do this by going to an individual client profile, clicking on ‘Export‘, selecting the data you want to download and then clicking the button that says ‘Export‘.

The following pop-up will appear:

As soon as your download is ready, click the ‘Download‘ button to download all the data.
A ZIP file with PDF documents will be downloaded to your hard drive.