Hi Ned,
OK, some ground rules. You said car so I’m going to discount SUVs and off-roaders. You didn’t specify not an estate so let’s go for one. And then the answer is easy – Mercedes-Benz E-Class Estate with 695 litres of boot space with the rear seats up. It expands to 1,950 litres if you fold them flat, but there are other cars which can match that.
If you fancy something more affordable but still cavernous, then go for the Skoda Superb Combi estate (which in so many ways is an E-Class for half-off…) which boasts a 633-litre boot (seats up) or 1,865 litres (boot down). If you fancy something a shade more affordable then there’s the Honda Civic Tourer estate with 624 litres (seats up), or 1,668 litres (seats folded).
OK, so you want an SUV included? How about a Land Rover Discovery? Fold down the third-row seats in the boot and you’ve got a whopping 1,124 litres to play with. Need something cheaper than a Discovery? How about a Ford Grand Tourneo Connect? It’s not a car we could heartily recommend from a point of view of comfort or driving pleasure, but it does have a whopping 1,264 litres of boot space.