car vs train for 8 trip to austria

Its a depender.

I refuse to drive on holiday, much less drive a van with 8 people in it. Then there is the drop off fee, tolls, gas, parking cost, tickets, accidents, missed flights due to imprisionment, the usual.

You could maybe rent private transfers for the cost of the train tickets since you have 8

You also might look at daytrip.com and see what they have

otherwise I would find a good travel company in Austria and get a quote.

Or take the train

The itinerary is relatively straightforward... Ideally a car rented for driving in Austria only might be cheaper than 6 train tickets.... but six adults (with luggage!) will probably need two cars since European models are usually much smaller than those to which we are accustomed. Also any trip for a group of six over 8 days will be limited by the slowest person involved for whatever reason... preference, illness, etc. One can always catch a later train to meet up at the next hotel. And you can't blame folks for having their own travel styles. For example I normally get a long "case the area" walk on many mornings in a new city while my partner sleeps in. You know these folks so it is something to be discussed among you now. I recommend the train option for flexibility.

Take the trains: Vienna to Salzburg 2.5 hours; Salzburg to Hallstatt 2 hr; Salzburg to Innsbruck 2 hours.
With your itinerary, you could easily add Berchtesgaden National Park which is 90 minutes from Salzburg by bus.

With the destinations you listed in an 8 day itinerary, the train will be more efficient, more comfortable, and likely more cost effective, than renting 2 vehicles with all of the costs and burdens involved with rentals, including drop off fees, fuel, parking, tolls, red light camera tickets, mystery parking tickets, etc. Plus you really do not want to deal with vehicles in Vienna and Innsbruck...

https://www.kayak.com/Vienna-9-Passenger-Van-Rentals.22046.9-lcv.ksp?r9ck=iq&gad_source=1&gclid=Cj0KCQjwqIm_BhDnARIsAKBYcmsnvfJFHnUEbJf4jzx22xpyLSSk_wM-ULT3OKUFvoZKt2jfzwq5kiQaArUAEALw_wcB

If your group can coexist for 8 days together in a passenger van, and someone is willing to drive, this is almost certainly the least costly approach. As for Salzburg, it's really not a terrible city for driving, outside of the Altstadt. Staying in the vicinity of the Volksgarten or along the Aigner Strasse would be driveable, with an easy walk or bus to the tourist areas. And driving to Hallstatt would be far preferable IMO to the silly process of taking the train and associated ferry. There's ample paid parking in Hallstatt.

Vienna, of course, should not be driven into or through. Innsbruck is a city I don't know.

8 days, 4 locations. Not much time in any of them. I think you’ll be tired very quickly of traveling that much and not seeing much.

I’d split the time between Vienna and Salzburg and the area around it. For instance you could base in St. Gilgen. Easy bus to Salzburg and the same for visitng Hallstatt. You could also include Werfen and the Ice Caves and the Castle/Fortress there.

https://www.salzburg-burgen.at/en/hohenwerfen-castle/plan-visit/openinghours/

https://www.eisriesenwelt.at/en/

2 or 3 nights Salzburg, 1 or 2 nights Hallstatt, 4 or 5 nights Vienna.

My choice, 2, 2, 4