Lifestyle tips

It al really depends on where your seat is set at for some of it. I have a 19 optima and my belly still haves room. But I'm tall and my seat is all the way back and leaned back some for head room.

Jeep or most larger suvs

How about using a trailer? They are available in various sizes and load capacities
(ducking and running )

some of the older ford falcons, mid 00's volvos but their roof can be low on some models.

Look at Minivans. Perhaps a Toyota Sienna or Honda Odyssey.

Try a older 2014 or older Kia Sedona

I have a 2004 Nissan Xterra and at 425 lbs in was hard to get in and out of.
I had a 2009 Mustang as well and it had plenty of belly room but at that weight my hips rubbed the door and the console.
I have a Jeep Wrangler as a daily driver now and at 360 ish it has plenty of belly room and hip room.

There is a pic of me in my Xterra in my pics section.
I don't remember what my weight was but it was getting to be a tight fit.

I haven't fit in it for a while now.
I do start it up every week or two my neighbor drives it when he needs it to haul something for his wood shop.

My partner who's a feedee and a car salesman recommends looking into a Kia Sorrento. Other options include pickup trucks with a bench seat or a Mazda CX5. Basically you're gonna want a good ride height that'll be easy on your knees--you want to be sitting, not squatting. But if you really want a sedan, a Chrysler 300.