Can I start as a private person?
Yes. No KvK number is needed. Your name and email address, a business name, your country and your trade are enough.
When do I say if I am a private person or a business?
When you set up payments in ServeCounter. The Payments step asks whether you are a private person or a registered business. If you have a KvK number, you enter it there.
Where do I see my KvK number later?
Under Business details, read-only. It is taken from Payments.
Where does the KvK number show?
Receipts and invoices show your KvK and VAT numbers once they exist.