Each one gets its own overview. A company's accounts are Business by default and a person's accounts are Personal by default. You can still change any single payment.
Link every account to its owner. Your own statement accounts show up here after you load a file. Add other accounts too (for example Kätlin's or PKS Holding's), so payments between them show who is on the other side. A default category sends all payments to or from that account to the category.
Everything you load is kept on the server by payment date. Open a month, export it as CSV, or delete it.
Payments, links, categories and remembered choices are saved in the server database. Download a backup now and then.