Travel from Minneapolis to Naples in October

I don't buy tickets that far in advance because the airline schedules often change, sometimes multiple times. The only way to know that it's a good fare is to track fares over a number of months. Under $900 doesn't "sound" bad at all but 1) October is not exactly peak travel season, so there's no reason to feel a rush to bite and 2) the connection times don't sound super attractive. I would personally hold out for something better (taking into account connection times and weighing them against the price), and you have a lot of time to do that.

One alternative you may consider is a round-trip ticket to Rome. Flying into Rome is generally cheaper (it's a larger market for US-based flights), and it's only a 2 hour train ride to Naples from there.

While the price doesn't sound bad, the fact that it's on two separate airlines is concerning. If there is a problem with one flight - delay on arrival/departure - the other airline won't care and isn't obligated to make alternate arrangements.

As suggested above, I'd consider flying in/out of Rome and then taking alternate transportation to Naples.

You can certainly arrange flights with shorter connections. Or, rather, Delta can. Minneapolis is a Delta base. Flying across the Atlantic it operates with KLM as almost one airline. Transavia is a subsidiary of KLM. So either Delta or KLM can book your complete itinerary. The trans-Atlantic flight will probably be pooled -- that is, operated by Delta, less likely by KLM. Doesn't much matter. And it doesn't matter who is operating the short European hop. Your flights will all be on one itinerary, with automatic luggage transfers (and frequent flyer points.) Probably the boarding passes will be issued at point of origin (seat selection may depend on the operating airlines.) If there is a delay, the airlines will put you on another flight.
I doubt you can save enough money by booking individually to make up for the extra hassles such as rechecking bags at the transfer.

I've left out the part about Amsterdam sightseeing in a hurry. Not worth it to me. But it can be done, booking through a multi-destination search function, not individually.

PS: Go directly to the airline to buy tickets and make seat selections.

While the price doesn't sound bad, the fact that it's on two separate
airlines is concerning. If there is a problem with one flight - delay
on arrival/departure - the other airline won't care and isn't
obligated to make alternate arrangements.

That would be my concern as well (and I live in a Minneapolis suburb). We routinely pay per-person over $1000 in airfare from MSP to Europe but we also book on one airline+ their codeshare partners (such as KLM, Alitalia, etc for Delta) in case anything goes wrong plus it makes the layovers smoother. Our bags check all the way through if our flights are with a partner.

I would sure hold out for a Delta/KLM/Alitalia/Air France single ticket if I were you, even if it costs a little more. Especially if you plan to check any bags.

Are your dates in October flexible at all? It looks like the fares drop under $900 during the latter half of October.

Thank you all; this is great information! We are on a tour with set dates. I'll keep watching and look into flying into Rome.

Mary, it sounds like budget is your paramount consideration. (I'd never accept a 22-hour layover.) But if your tour departs from Naples (where does it finish up? Do you know what an "open-jaw" itinerary is?), it's worth extra money to be delivered to Naples. There are plenty of (two-seat) trains from FCO to Naples Centrale rail station. But the fast ones from downtown Rome to Naples have to be bought in advance and can't be changed or cancelled. What are you going to do after the lobby of the Naples train station?

Although you have given a lot of information, you left out the tour package in your OP. The reason I mention that is that you might get better advice if you described more of your plans. For example, coastal areas everywhere tend to slow down in October. Local bus and ferry schedules can move to less frequency, and some ports may no longer have ferries. But if you are simply meeting a tour and have no independent plans, maybe it doesn't matter. Decreased attraction crowding will be a plus, but check the number of days with rain. The ocean temperature is never very warm around there.

I agree that you should try total ticketing on your preferred airline site before you get into mix and match. Because of the post about KLM, I would suggest you find out what KLM flights are code-shared and try them on the KLM site as well. It might even pay to join the KLM FF plan to see if pricing or availability is better. Is earning miles a factor at all? Read our host's air travel advice, top left menu, Travel Tips.

I would also think about (as somebody else has suggested) flying into Rome and taking the train, I have started my past 2 planned trips by flying into Rome and taking a train to the Naples area. I know the Alibus (from the airport to the station) isn't that much hassle, but if I can step off the airplane and almost directly get onto a train with minimal "schlepping", I am all about that. It might end up being cheaper for flights as well. From Minneapolis, you might be able to get a nonstop somewhere as well.

Its not usually a great idea to book on separate airlines on separate tickets, so I would try to avoid that as well. If you are on a more budget airline for the European leg, you might have to pay for more luggage on top of the not guaranteed tickets.