Hi 👋 Sven-Magenta-Wolf-2549297928
Great to hear you also want to manage your business through bunq. 🌈
To answer your questions, yes you can manage both accounts from the same app. By hard/long pressing the 'profile' button on the bottom you are able to switch quickly between multiple accounts. This is also where you can find the possibility to open a new business account, under 'more options'.
As of the pricing, your bunq Premium membership of €7,99 will be billed from your personal billing account. The business membership of €9,99 will accordingly be billed from the business account you have setup for billing, these are both separate accounts.
If you have any further questions let me know.