For cheap a rover 800 fastback (5 door) i fetched my first C5 with my 800, back seats down but no bases out and still a lovely car, get the vitesse then you have 200 hp and a big turbo to boot, scares the boy racers off the lights. I still run an Rover 800 sadly not the 5 door but a far rarer 800 coupe.
Then to a range rover, where the C5 had to sit on the roof (to go to a land rover show of course)
Now vauxhall monterey LWB (isuzu trooper) 2 in the back and 2 on the roof (4 up) is possible, leather seats lots of comfort. Tons of power.
Also have a 1955 austin A30 but i think the C5 is faster than that