The German bureaucracy does not seem to appreciate Marie Kondo. The retention period for essential documents is ten years.
Tax documents, craftsmen's invoices and insurance policies should be kept for a limited period of time. There is a wide range of options available from around ten, to high-end shredder attachments. All five models tested are relatively similar in their functionality, but in some cases have significant differences in their price. All are extremely far apart, apart from the Leitz as up to eight hours for occasional users.