Dog-Car Equipment

Hello dog people

I am going to get a dog and I’m buying the dog equipment now. I notice there is a PLETHORA of dog-car equipment and I’d like some help deciding what to buy.

I will have to drive the dog 4hrs to bring her home. She’s a pretty big dog.

Once I’ve got her home, I imagine I’ll transport her in the car every few weeks.

I currently drive an old Honda Jazz (small square car, surprisingly roomy inside). I’ve been driving around with the back seat folded flat down because I’ve been moving big items of furniture in it. That got me thinking maybe I’ll just leave the backseats folded flat down, and put a waterproof mat down, and transport dog that way?

So – what’s the best option?

Leave the backseats folded flat down, or flip them up again? Harness plus seatbelt clip thing? Or one of those wire car dog fence things? Or something else?

I know it’s not a life changing decision but I figured if I’m buying new stuff anyway I might as well do it in a considered fashion.