From my experience, no paperwork is needed for remote contractors - I just send PDF invoices at the end of the month and that's it... Money is transferred throu

From my experience, no paperwork is needed for remote contractors - I just send PDF invoices at the end of the month and that's it... Money is transferred through bank/wire. I've had clients from USA, several European countries, Asia, ... So I don't think Swiss laws are much more strict (e.g. compared to USA) regarding buying services from remote companies/consultants.