My niece has twins and is expecting a third child. What would be her most cost-effective choice for a car that would allow three car seats across?
The most cost effective is a Ford Crown Victoria used. However make sure she tries three seats across.
Otherwise my strong/best suggestion would be any minivan of her choice. They are the best vehicle for 2+ children.
I think your niece should consider a minivan. It could be used for long trips where either mom or dad sit in back with the children to keep them amused. If the kids are three-across there will be fights. A minivan can keep some space between them and some sanity among the parents.
If it has to be a car, any full size car will do. Your niece can take the seats and install them to see if they fit. That’s a must if she seats them in one seat.
When you start talking 3 car seats, it’s really hard to beat a minivan for hauling capacity and loading ability. They are much maligned, yet so stinking practical. If they need to go with a used vehicle, they should try to go with one that is 2001 or newer. The reason for that is the government mandated latch system for securing child and infant car seats. The system is much better for safely securing the seats than vehicles without.
Crown Victoria or Grand Marquis and full size pickup truck. Just take the kid in your car. Wouldn’t want that diaper so close to me. Signed. The original gutless wonder.
The other advantage with a minivan is that if you go on any kind of trip you can easily haul the play yards, strollers, luggage, etc, and everyone (including the kids) travels comfortably.