Would need to rent one to ferry a group of people to/from a teaparty. Anyone has any tips or a minivan to rent?

Depends on how many people. With a normal drivers license you can carry up to 11 including the driver, not 12 + driver as in the rest of Europe.

You can get 7 seater minivans from Mobility (www.mobility.ch) or you need to rent a van.

I don't know where you are, but if you are in the Baden/ZH area I got a minibus from Extragent (www.extragent.ch) who were fairly reasonable.

The big rental firms are expensive, particularly if you rent from the airport.