How best to transport my dog in i3

I am shortly to take delivery of an i3. I currently use a wire crate in the boot of my Civic to carry my dog, but this is completely infeasible in the i3. What alternative options are there to keep the dog comfortable and safe? The dog is a Border Terrier, so small-ish (10 kg).

Any advice welcome.

How big is your crate? Sized right, a dog crate should be just large enough for the dog to stand up in and turn around. They are supposed to be their small cozy den, not a play-pen. We used a soft-sided travel crate for our 10kg French Bulldog, and it fit fine, Though most of the time she just rode in the back seat, with a harness that snapped onto the seat-belt.

https://www.amazon.com/Noz2Noz-Soft-Krater-Indoor-Outdoor-Crate/dp/B000P9XMMY/ref=asc_df_B000P9TNLI/?tag=hyprod-20&linkCode=df0&hvadid=167132165277&hvpos=&hvnetw=g&hvrand=10020580579772288737&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9026839&hvtargid=aud-801381245258%3Apla-307860424479&th=1

https://www.kurgo.com/dog-harnesses/enhanced-strength-dog-car-harness/

Hey Imp,
We have a Glen of Imaal Terrier who weighs about 15 kg. She rides in the backseat inside a K&H Travel Safety Pet Carrier (https://www.khpet.com/travel-safety-carrier.html). I have one in my 1-series as well. Got the first one from Amazon but they were out of stock when I tried to purchase one for the i3 so I got it from a national pet supply retailer here in the states. The rear seat belt slides through a strap on the back of the carrier. There is also a small strap which goes up and around the rear headrest. Very secure and she is perfectly happy in there.

I don't understand why there's no pet carriers than use the (mandated in every car since 2002) LATCH points.

I purchased a back seat 'hammock" similar to this (the model seems to have changed slightly)

https://www.amazon.com/SUPSOO-Waterproof-Durable-Anti-Scratch-Protection/dp/B07TV1YMF3/ref=sr_1_1?keywords=SUPSOO+Dog+Car+Seat+Cover+Waterproof+Durable+Anti-Scratch+Nonslip+Back+Seat+Pet+Protection+Dog+Travel+Hammock+with+Mesh+Window+and+Side+Flaps+for+Cars&qid=1584071850&sr=8-1

of if the link doesn't work search for "Dog Car Seat Cover Waterproof Durable Anti-Scratch Nonslip Back Seat Pet Protection Dog Travel Hammock"

It fits pretty well in the i3 and works great for my 50 pound dog (23 kg). It stinks like manufacturing chemicals, so wash it first and leave it outside - not in your car - when not in use.
Tip - close the front door before you ask your dog to jump up! My dog was totally muddy after a hike and the front door space is much wider than the back - in my other cars he'd jump into the back, but a combination of how the doors open and the wider front door - he jumped straight into the drivers seat and got mud all over. Doph!

The dog is loose of course, so you may or may not choose that option for that reason