3 across - 1 in booster
Expecting #3, older siblings will be 8 and 4 when the baby is born. Oldest is already in a booster seat, and the soon-to-be middle sibling is in a forward-facing carseat. I see tons of articles on-line about 3-across car seat configurations – what are families doing with booster seats? It seems like with 2 car seats in the back, it'd be very hard for our oldest to reach the seatbelt buckle.
Before you say minivan – no. We live in a walkable city & street-park our car. This means we routinely parallel park in very tight spots; it's not uncommon to drive around for 10-20 minutes looking for a parking spot. Our Mazda CX-5 is 180in long; a Honda Odyssey is 205in long. The extra two feet of length would make it significantly harder to find parking, and we'd probably need to shell out $600/month for a parking spot.
If we won the lottery & could buy a house in our neighborhood with a driveway, a minivan would probably be my 2nd splurge, after the house itself.