In my experience I would have to say either every Ford or every red car. I know neither make sense, but I won't be having either again, if I can help it. Overall I would say the least reliable car ever built was the Triumph TR7.
Cant comment on fords, never had one, but regarding red cars, years ago (in 1993) had a red 1990 cavalier 2.0cdi, bought it with 84k miles at auction, , p/xed it 1998 with 204 k miles on it for a cav v6 cdx (which i wish i still had). In 120 k miles, the only things (apart from consumables such as cambelts, pads, oil/filters etc) I had to replace were
1) headlight lens, £8 new, 15 mins work
2) handbrake cable £15, 1 hrs work
3) battery, £40 , 10 mins
4) alternator, £60ish, 1 hr
5) half an exhaust, £80 at fast fit centre
not a lot for 5 years and 120k miles is it, and the car never once left me stranded. Not the most exciting car, but was great for long journeys, would do 40 mpg sitting at 85mph, and would go off the clock when wound up