$3600 looks like a good price; your only better option on price is to fly into Milan, which is showing $2880 R/T for four people for mid-June dates. Not a terrible itinerary either, with TAP. Hard to say if anything will go lower on price. At this point, with inflation and travel demand in 2024: I would say under a $1000 R/T per person is pretty good for SFO to specific area in Europe at this point.
We've only purchased "extra" travel insurance (travelguard) a couple times - Australia with infant twins, Kenya during a presidential election. We always have a quiver of cards, including a Sapphire, which cover any issues with delays, lost bags, etc etc. Rarely, if ever have had to use it, but we're usually on flying on miles, so we're not as concerned about recouping $5000-10,000 in greenbacks if things go south. Definitely have a Sapphire or similar card with good benefits and book all your flights, cars, hotels on that card.
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