Greetings,
I'm planning to go to France with my children next year. We'll be six people plus my SIL who is coming along (so seven total, but she'll pay her own fare.) We live in Charlotte, NC and we will be staying in Limoges. (SIL lives in Atlanta) It will be a long stay, so I can be somewhat flexible on the travel arrangements. I have had globe trotting friends recommend flying out of other cities (esp Miami or Toronto), connecting through other countries like Iceland or Ireland or Netherlands, etc.

While trying to find the balance between budget and complexity/exhaustion, how can I find the best airfares given how many variables I am willing to consider? Do I just have to check various airlines and cities by brute force or are there some tried and true websites that can help? Or Set up multiple email alerts? (Which site?)
For example, I could rent a car to drive to Baltimore, stay overnight, then fly out of Baltimore to Paris or another city? Then take a train or pick up a leased car and get to Limoges? The plan is to depart the first week of August 2020. Thanks in advance.

I dunno... I think I'd KISS, but I've never had to buy that many tickets. I can't imagine a fare scenario where renting a car (one-way surcharge? plus gas) and paying for 2 hotel rooms would be more economical overall. But who knows? I think I'd work with a travel agent who can search multiple options at the same time, knows the fare trends, etc.

How old are the children? One thing I do know is that I wouldn't want to be puddle-jumping my way through multiple airports with little kids and lots of luggage. These days, air travel is hard enough under the best of circumstances.

Fwiw, I am thinking of leasing a car so I'll have it for the entire stay.

I was thinking of the car rental from Charlotte to Baltimore or whichever city has magical airfares.

Yes, true. I'll have to price it out further, but I figure if I save a few hundred dollars per ticket flying out of another city within driving distance, it would be worth the rental, but with a hotel room too (or two), might be diminishing returns...

How old are the kids? The younger the kids the simpler you should keep it. Obviously if they're teenagers they can handle more but do you really want a Home alone situation?

Renting a car to drive to another city sounds like an expensive pain in the backside that I would not consider unless it saved a whole lot of money after factoring in the expense of the rental and the annoyance of the drive. Plus, to accommodate six people with luggage you would likely need a van. Not a pleasant way to start a European trip, IMO.

CLT is an American hub, and you can get nonstop flights to Paris with them. Atlanta based sister can fly to CLT a day ahead to join you all or just fly out of ATL and meet up in Paris. From Paris take the train to Limoges. Best connections leave from Gare de Austerlitz so you would need to arrange transport from CDG there. With the size of your group taxi is the least expensive as well as easiest option - just walk to the licensed taxi queue and wait for two minivan vehicles which are fairly common. There's a direct train that leaves about 2:30 which would give you time for lunch in Paris if jet lag permits. Could even spend a day or two in Paris before heading on to Limoges.

Most airlines will not consider group discount for less than ten people, but it may be worth your while to contact AA and see what they might be able to do for you . Worst case, they say no.

You have to use multiple methods. You have to understand that the pricing is market based.
I see variations due to departure dates, route, marketing channel differences. Certain date combinations are inherently more expensive than the others. There is no one rule. You have to do a lot of what ifs to find out which flights they need to go soft on price to entice price sensitive leisure travelers.
Similar tickets bought from the operating carrier e.g. American, vs. code share e.g. BA, can be sold at different prices. Of course, the terms and conditions differ.
I think RDU is much closer alternate airport than the ones you listed and often offer lower cost flights than from CLT. I think AA has the marketing power at CLT as it offers unrivaled number of non-stop flights to Europe. Of course AA seems to capitalize on that position. RDU has limited non-stops to Europe. I think Delta and AA offer one non-stop route each. But they need to compete, which is a good thing for passengers.
https://www.flightconnections.com is a good site to find out which carriers offer non-stops from a chosen airport.
Google flights sometimes list good prices on flights marketed by a code share but on a specific flight/date combination.

Time of year is a major price factor; summer is more expensive trans-Atlantic. Let a search site put together an itinerary for you rather than pasting one up yourself.
In my unscientific experience, you can find the most air choices at matrix.itasoftware.com
It's a Google company but doesn't sell tickets. With its information you can buy direct from the airline you choose, the safest and cheapest source.
American flies non-stop from Charlotte to Paris. Renting a car, buying hotel rooms etc. will cost money, waste time and subject you to substantial stress. Not a good way to launch a vacation.

https://matrix.itasoftware.com/

Whatever you do do not drive to Limoges on arrival. I don't care how well you sleep on a plane, just don't do it.

I sure wouldn't want to start off a long-haul vacation with that many people by renting a car, driving to another city, and spending the night. Even if that means you could save some money, which I doubt, for me it would launch the trip on a very bad note.

Seamus's explanation of how to get to Limoges is spot-on. I've taken that train from Austerlitz many times, and it's pretty easy (it's not a TGV, though). I believe you can get group discount tickets on SNCF, though I have never done that. Take a taxi from CDG. The attendant there will find a van that will fit all of you, assuming you're not burdened down with luggage, in which case you'll need 2 taxis and the train experience will be difficult.

Finally, I have to ask - why Limoges for a long stay? You must have a good reason, like relatives there, I assume, because it's hardly a sweet spot in France.

This is probably good advice. But if I lease a car, I think it will be best to pick it up in Paris. I am also looking into flying to Lyon instead. But perhaps I should plan a hotel stay for the day of our arrival then complete the last leg to Limoges.

If I am going to layer on traveling to various cities by car, I think I could better handle these complexities on the front end, i.e. State-side where I am more comfortable and familiar with everything, and I won't yet be super tired. I'd rather pay for the convenience and simplicity upon arrival in France. ...I really feel the tension between simplicity and budget and go back and forth a lot in my mind. Yes, I'll be travelling with kids and we'll be tired, and I'm willing to pay for conveniences. On the other hand, I have to multiply everything by SIX and that cost will add up fast.

I am planning a study-abroad experience with my children. As for Limoges, it is sister-city to my city (Charlotte), so I decided to set my sights there, as I do not really have any special connections in France, (although I did study and then worked there about 20 years ago in other cities) and the sister-city thing was better than nothing. So far, it has worked, now I'm getting down to brass tacks of planning logistics.

<<But if I lease a car, I think it will be best to pick it up in Paris.>>

Why on earth would you think that? If you do rent a car in Paris and attempt the long, boring ride to Limoges the day you arrive, at least warn those of us in France so we can stay off the roads that day.

The sister-city thing makes only a tiny bit of sense to me. Limoges is NOT even in the top 300 places I'd choose to take a family for a long visit to France, for oh so many reasons. Have you researched the place?

How long a stay? You are aware of the Schengen rules I hope.

Flight Charlotte to Paris: 8+ hours
Pre-flight check-in and security: 2-3 hours
Post-flight luggage retrieval, passport control, car leasing process: 3-4 hours? Longer?
Drive to Limoges: 5+ hours without stops

Time for a reality check.

BDKR's recommendation of ITA (post 11) is the way to go. https://matrix.itasoftware.com/ This is the gold standard for finding flights; while you can't buy tickets through ITA, it will link you to Google Flights (ITA got bought by Google a few years ago) or you can just go to the airline that comes up with the best deal on the search. Learning how to use ITA is well worth your time; it's very powerful and flexible. ITA will do all the work for you, sorting out various carriers and routes.

I just had a look at next August, using ITA's 30-day search, and putting in a couple of different starting points with Paris as the common destination. You don't say how long you'll be in France, but I put in 30 days for a drill. Generally I don't like suggesting that people fly from someplace other than their "home" airport, but in this case I found some pretty major differences that would lead me to suggest flying out of Raleigh-Durham rather than Charlotte if you bought your tickets today. In early August 2020 I can see economy fares in the $820 range from RDU; on the same days tickets were closer to $1200 - $1300 if departing from CLT. You could, for example, rent a vehicle in the morning from CLT and drop it at RDU in time for the evening (nonstop - Delta) departure to Paris, and save several hundred dollars - maybe a couple of grand - in the process. (Note fares were below $700 for some days departing from Dulles airport in Washington, but it might be a close thing to schlep there, and would add considerably to the fatigue factor.)

As for ground transportation, again, as a test, I looked at Renault's leasing program ( Renault Eurodrive, short term Car Lease Program in France and in Europe, Car rental in France and in Europe, Long term car Lease in France and in Europe, Discount car rental in France and in Europe, One way car rental, One way car lease, France, Euro ) and also at Expedia. Again, not knowing how long you plan to be there is a barrier, but for a 30-day rental of a minivan (Renault Scenic) with pickup at CDG, Expedia (Hertz) was $700 cheaper ($1438 v. $2120) all in than the Renault leasing program. However, if you want to pick up and drop off in different places, the gap might be narrowed or even eliminated. I would probably book an airport hotel or something close to CDG for your arrival day; braving traffic after a likely sleepless night (and a long day before) doesn't sound like a good plan to me.

To be frank, with as many variables and alternatives as you'll be presented with, I'd probably be tempted to book the airfare and vehicle sooner rather than later, and get it behind you. If you wait, you MIGHT save a few bucks on airfare, but then again you might not. Without getting into the weeds on how airlines allocate their seats into various fare "buckets," I'll just say that getting the cheapest deal with six passengers on one ticket is harder than with two or three, so the risk of having the total cost go up with a big party is higher than with a smaller one.

I'd also probably buy some trip insurance in case something goes sideways over the next 10 months; the risks v. savings might be worth it.

Happy planning!

A Scenic would not be big enough for 7 people and their luggage. Also possible car seats/boosters needed depending on the age of the children involved. Either two vehicles or a minibus are needed.