I thought this might be useful to someone in the same position as me :)
One of the first things I was concerned about when we found out I was pregnant with number 3, was how I got all my children safely in the car. And maybe squeezed my husband in too. I didn't want to be driving a huge car like a VW Sharan but I couldn't fit three car seats across the back of my Vauxhall Vectra. I did do a vast amount of research into which cars could fit three car seats across the back but there didn't seem to be many. The ones that weren't massive were too expensive for us as well so I accepted that Elizabeth would have to sit in the front. Luckily we could all be in Frans' car when we were going out as a family.
Now that Zachary is here, I've had Elizabeth in the front with me in the Vectra but I really haven't liked it, for lots of reasons. So I've been persuaded to get a new car. I spoke with some of the mums at school as a lot of them have a Vauxhall Zafira so I thought that might be the car to get. They all said that they couldn't get three car seats across the back and had one child in the boot (where there are 2 extra seats). Well that was no good for me! I need to be able to get the double buggy in and the dog sometimes. There were various other cars that came up in my research but they were either huge vehicles or lost space elsewhere - like the boot.
I happened to try out a friend's Volkswagen Touran and three car seats fit! Nothing on the internet mentioned the Touran and none of the mums at school had one, which really surprised me. Not only can i fit my three car seats next to each other but the car is very versatile with so many seat configurations. And hiding spaces. LOADS of hiding spaces!
So now I'm driving a VW Touran. It's not my ideal car - I really didn't want an automatic - but it suits my needs perfectly right now and I guess that's what's important. Throw everything in and hope I've not forgotten something.