I am just starting to look into a possible late-summer trip with a family of 5 (2 adults, 18yo, 16yo, 15yo). Normally when we travel, we will home-base out of a central location for 5-7 days to explore and do day trips, typically in rental houses/apartments instead of hotels. Reading through different forums and itineraries, it sounds like this might not work so well in Iceland. It seems like most trips have more frequent moving around. Looking for some input on logistics behind travel with a larger family. The kids are all tall, and an SUV doesn't work very well with our luggage and them having to squeeze into whatever space is left. Are mini-van type vehicles common in Iceland? We have been in some other countries where they are basically non-existent, and the biggest vehicle you can find is a 5 person SUV.
You are correct that staying in one location is not the best use of time in Iceland.
As for a vehicle, on one of our trips we brought our adult kids. So 5 of us, like you. We had the 5 seater Land Cruiser so that the third seat was removed. That gave us plenty of cargo space for our duffel bags and day packs. Duffel bags are easier than suitcases since you can be flexible with packing the cargo area. FWIW I can’t remember ever seeing a minivan. We have been many times and have seen the Land Cruisers and then the larger vans. I may have missed them though.