I did rear-facing all the way to booster x2. We put the rear-facing kid behind the passenger seat so the driver would have the legroom.

There are a lot of strollers that will fit in the trunk. I don't know about those SUV size strollers that take up entire aisles in stores. You know the ones you can use to help your friends move. We used one from Combi that folded left to right instead of wheels to handles.

So do I, gives the girls more height to look out the window.

You should be fine. Ive managed to put a stroller in the trunk and car seat in the back no problem. When my nephew is old enough ima get this to put in my car