mc510

Very early stages of planning this family trip (two adults and two kids) for early June 2019, and I'm hoping for some advice on my flight search. Ideally we'd like to add a couple of days, on the way back, in another European city; could be almost anywhere. Flight cost is pretty important, since there are four of us, and airline quality/comfort matters a bit too since it will be a long flight with kids.

I've been rooting around in ITA and Google Flights and Skyscanner and they all show different results ... and that's without even getting into wanting to add a stopover or open jaw. I did an ITA search where I specified a return-flight connection point at some major airports that might make good stopovers. It gave a pretty short list of results at quite high costs, and didn't even include the flights that it originally produced when I didn't specify connection points, which leaves me not very confident that ITA is casting a wide net for best flights (and that's without even knowing if stopovers would be permitted). For a couple of ITA flights I looked at the rule, which say that stopovers are not permitted. And then I threw my hands up and said, this is one for FlyerTalk.

So I guess my main question is whether there's any particularly good way to search for SFO-ATH flights that allow a stopover or open jaw? And what about the advisability of searching for this flight now, rather than several months from now ... do airlines relax fare rules, or add seats under different fare rules, as you get closer to the actual date?

[EDIT] I'm playing around with Skyscanner's multi-city search, just experimenting with different cities where I might stopover. It's showing good options (almost as cheap as the cheapest direct flight) that are all on Iberia, and every other airline is at least twice as much. Is it possible that only Iberia currently has a fare that allows stopovers? [/EDIT]

[EDIT2] Wow, ITA can't even recreate any of the Iberia routings that Skyscanner is coming up with for a multi-city routing (stopover in MAD) ... gives three and four segment flights on SFO-ATH leg?? ... cheapest being 2X of Skyscanner ... which Skyscanner routing is sold by exploretrip.com, which I've never heard of and ??? [/EDIT2]