17 days total; 10 days in Switzerland, need to see Auschwitz, and Berlin. Need some advice.

You will have to do the math by looking at the cost of a RT air ticket plus the cost of the additional travel back to your start point, and then take note of how much time waste occurs in travelling back to your start point. Then compare it to a multicity trip arriving in one city and departing from another. Instead of going back and forth between Berlin and Krakow (Auschwitz), have you looked at arriving in Berlin, then going to Krakow, then flying to Zurich?

I think you could make it work either way. I also think you will probably find that you could have an open jaw ticket where you fly into Zurich and out of Berlin without paying a premium.
I like the idea of going to Switzerland first. Switzerland will be an easier adjustment than Poland or Berlin. Then at the end of that part, you either get a cheap flight or take a train to Krakow, which is 1 hour away from Auschwitz. Do Auschwitz, And then get to Berlin, either by train or by plane -- there are some very cheap flights with Ryanair. I don't know about renting a car. That seems like more hassle. Then you visit Berlin at the end and you fly home from there.

I agree with the above, that flying open jaw is not usually more expensive, in my experience over several trips and over the years.
Safe travels!

If you are going to Auschwitz I recommend you spend a little time in Krakow too. Wonderful city!

Thank you so much for the replies here. It's already helping me zero in on how best to navigate this. Before posting this thread I was toying with adding in Amsterdam to this 17-day trip but I've been properly told that it's best to keep it to 2 countries, max, and I'm liking the thought-starters!

I too think flying open jaw, into Berlin and out from Zurich, or vice-versa, makes the most sense. But I suggest the trip should start with Berlin so the Switzerland portion is at the end,mas late as you can make it, for weather considerations.

I just did a quick check on rental car prices for a drive from Berlin to Auschwitz, returning the car at Krakow airport so you can fly to Switzerland. For a 3-day rental (the minimum) for a car that seats 5 comfortably (and hopefully has room for your luggage) they came up with $1600 with an Avis rental. I think that includes the one-way fee for dropping the car in a different country, but you would need to confirm that. And you need to add the cost of petrol.

By contrast, train tickets from Berlin to Auschwitz state around €39, and there may be a reduction for 5 traveling together ( I don’t know the German train deals but I believe they do exist for families). You would have to check prices for a flight from Krakow airport, but that would be the same as it would if you were driving.

Secretly, I am wanting to really enjoy the public transportation offerings of Europe. My default impulse is to just rent a car and I'm thinking I should just lean into options that would give the family the best possible experience. (I'm saving my reveal of Rick's recommended packing list until we're fully booked. I'm genuinely anxious thinking of this family believing they can bring steamer trunks with them from the US. ;D )

Renting a car just to get from A to B is not something that Europeans do, so the rental agencies are not really set up for it. Hence one ways are rare, and when they exist, expensive.

Also don't forget that if "driving time" is 6 hours that travel time will probably be longer. If you are willing to put up with spending a day to get to Auschwitz then you can as well take the train, which will save you a bundle. And you will need that later for Switzerland :-)

When you write "the latest guidebook", do you mean Rick Steves Switzerland, or something else? I ask because Rick has so much general advice on visiting Europe, as well as single-country attractions. Just for example, your assumption that air round-trips to the same city are cheaper is quite obsolete. I recommend that you put a link to the first discussion in this thread, but that's just my opinion about newsboard organization, not some kind of rule.

Ten years ago, when I rented a car at the Zurich airport, I was told that I could not take the car into Poland. Luckily, I wasn't planning to. Remember that you need some country-specific stickers in German cities and on Swiss highways. Got an IDP? Read up on speed cameras? Specific car rental website research on second-country "drop charges"? You do appear to be making the American "mistake" of believing that a car is the best way to get anywhere.

simply make Auschwitz a 2-day detour before flying out

You do have a big group, but please don't have any illusions about how many places you're going to see from the highway, or how many picturesque villages you're going to drive 20 minutes off the highway (and 20 minutes back) to visit for an hour, on the way somewhere. Krakow is not next door to Berlin.

One idea would be to make a list of Google Maps distances, and then do a DB and Polish Rail search for the most likely train times. You need real facts to make these decisions. Berlin is a great-city of the world, and also a good war history place. But you're already up to three countries then. If you're not going to follow your own rule, fine. I've been to Berlin at least 4 times, but it's never been convenient to combine it with Poland. We flew NYC-Warsaw, and Krakow-London to visit friends, before flying home from London. (I think too many Americans include England on too many trips, but it seemed to make sense that year. Not directly relevant to your interests.)

Or, fly into Zurich, stay there for 10 days

Do you mean "there" in Zurich as a base, or "in Switzerland"? I ask, because if you mean sleep in Zurich 10 days, then you haven't read Rick's advice for visiting Switzerland yet.

The reason for visiting Krakow isn't because it's better than Berlin (may or many not be true, depending on your interests and ethnicity), but because it's a good base for Auschwitz. Auschwitz is an all-day project, with reserved times required, on THEIR schedule, with THEIR guides, followed by free time at Birkenau, usually. Many people don't want to go to the opera (made that up ... ) after a day at Auschwitz, even if they have the energy left.

I'm not trying to talk you out of Auschwitz, it's clear that it's a priority for you. I'm just trying to get you to use real data in your planning. If it is your top priority, then make it your top priority. I mean, Poland is a pretty good place to research WW II, isn't it? Did you have relatives in the US Army who were stationed in other countries during the war? It's just not clear how you picked Berlin, except that it's sort of near Poland.

Have you made a list of WW II sites that you specifically want to see? Then you can balance that time against your vigorous desire to spend ten days in Switzerland. (Business trips aside, my wife and I didn't go to Switzerland until we'd been to Europe 12 times, including Scandinavia. And I remember my grandmother loved Switzerland.)

You posted this once before - has anything changed?

https://community.ricksteves.com/travel-forum/general-europe/may-25-june-11-2023-for-family-of-five-poland-switzerland-germany-maybe-amsterdam-planning
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With only a few days in Berlin, you'll have to high-grade your WWII experiences - settle on the major stuff and take a pass on the one room, off the beaten path type museums.
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I agree with others, Auschwitz Birkenau is an all day outing by the time you return to Krakow - and saying that I wouldn't be giving short schrift to Krakow.

You have chosen Switzerland and Germany for your trip and want to visit Auschwitz.
You are ignoring Krakow, near Auschwitz, one of Europe’s most beautiful small cities. Take a deep breath and give Krakow at least two nights. Stay near Ryneck Glowny, the central square. We had a very good experience staying at the Amber Hotel Design a few blocks from the square. The hotel booked our guided English speaking tour to Auschwitz for us. Be aware that after spending time at Auschwitz you will be emotionally drained and quite tired. An extra day to enjoy walking around Krakow would be good. It wasn’t bombed in WWII and has retained its charm and beauty.

Are the women on board with the WWII stuff? Honestly, my daughter and I would not be happy about going to Berlin on our first trip to Europe. Did you consult the others about where they would like to go? I think there are other locations, such as Amsterdam, which the girls would like better and in my opinion, the Anne Frank House would be more relatable for them than Auschwitz.

We actually have done an open-jaw trip between Berlin and Zurich. We flew into Berlin and made our way via train to Zurich over twelve days via Prague, Munich and Salzburg. Open jaw saves SO much time, unless you are based in a city and your plans involve day trips from that city. I recall searching for flights Berlin-->Zurich and vice versa, and booked the combo that was less expensive, since it didn't matter which city we started in. Google Flights is your friend here!

Have you looked to see if there is an overnight train from Switzerland to Berlin? If you are jumping from Switzerland to Berlin or Poland, I would look into an inter-Europe flight. I love the train, but that would be a long trip by train and would eat up at least one full day, if not more, with travel.

Also, I would agree with others who say that if you are going to detour to Auschwitz, you should spend a couple days in Poland.

Lastly, there is plenty to do in Berlin besides WWII sites. It's a huge, spread out city so whatever you do, plan your time there well in order to avoid criss-crossing the city unnecessarily.

It is not always cheaper to fly in and out the same city IF you take into account the time and money that it takes to circle back to the arrival city.

Why not fly into Krakow and start the trip there? Krakow>Berlin>Switzerland (fly home from Zurich).

Who would I best be able to talk through this? A travel agent? A Switzerland-specific travel agent? I don't necessarily want to book through them; I was just hoping to get some undivided attention and honest feedback.

Professionals generally don't like to work for free. You can ask all the questions you want here in this forum and get good advice. And make sure all five of you read that guidebook, not just one of you.