Two Toyota
Two Honda
One Chevy
One Porsche
Motorcycle
10 Honda
1 KTM
1 Kawasaki
Two Toyota
Two Honda
One Chevy
One Porsche
Motorcycle
10 Honda
1 KTM
1 Kawasaki
One Subaru
One Toyota
One Toyobaru (?)
One Chevy
[Motocycles]
One Honda
One Buell
Two Suzukis
Gm x 3
chrysler x 2
ford x 1
kinda vw x 1
devin x 1
EMW x 1
datsun x 1
sunbeam x 1
infiniti x 1
could technically lump datsun and infiniti under the nissan umbrella
One Jeep
One BMW
One Toyota (SWMBO's)
If we add in everything else with an engine that's not a car, I've got:
One Ariens
One Honda
One Chris Craft (powered by 2 GM 454s and one Onan generator)
So at least currently, it doesn't seem like I own 2 of anything from a given brand.
3 Mazdas
2 Chevrolets
1 Honda
1 BMW
4 Prius, business fleet (for mpg things)
1 Ford F-250 (for truck things)
1 Dodge Grand Caravan (for van/family things)
1 Montero (for 4wd things)
1 Miata (for smile things)
I've had over 130 cars in 40 years, but never more than 10 at a time, and currently down to 3.
2 Chevys and 1 MINI. Over the summer it was 3 Chevys.
Mazda Miata
Chevy Suburban
VW Passat
Jag X-Type (which is a Ford in a tuxedo)
Zamboni (with a Ford motor)
Pontiac Fiero (with a Buick motor)
Not much repeat in that list.
Currently, it's 3 for 3: One Dodge (Dart), one VW (Passat), one Honda (Accord). Also three different countries of corporate ownership - although all three were made at US factories (Hammtramack, MI; Marysville, OH; and Chatanooga, TN).
I think the last time we had a duplicate manufacturer was about 10 years ago when my wife was driving an Oldsmobile Achieva and we had a Chevy Suburban for truck duties.
4 vehicles. Technically 3 manufacturers, but I'm saying 2. Hyundai/Kia are the same damn thing in my book.
GMC Sierra
Chevy C10
Hyundai Tiburon
Kia Rio
7 cars, 5 motorcycle.
2 ford
5 dodge
1 honda
1 yamaha
3 suzuki
20 throttle plates......
Fun. 5 vehicles, 4 manufacturers, 18 cylinders, 4 rotors, 3 turbos and 8? throttle plates:
Chevy Silverado (V8)
Ford Flex (Eco-Boost V6)
2 Mazda RX7s (79 with facory Nikki carb and 86 with ITBs)
Volkwagen Jetta (TDI)
I don't like to quantify my bad decision making with numbers anymore but i'll go as far as admitting i own 11 brands of cars. 
We're at 9 cars currently.
5 Saabs
1 Cadillac
1 Chevrolet
1 Toyota
1 Mazda
Chevy (1)
Ford (1)
Jaguar (1)
Audi (1)
Pontiac (1)
BMW (3)
Alfa (1)
Up until a bit ago I would have called myself a die hard GM guy.
"Car" can mean different things in context, so first I'll list the total, then some explanation.
Total cars - 17
Porsche - 12
VW - 3
Honda - 1
Toyota - 1
-------------
Porsche
VW
Honda
Toyota
----------
Six or seven years ago it was mostly Hondas with a couple Fords and Volvos (No German cars).
6 cars, 5 manufacturers.
Nissan: 2 Datsun, 2 Infiniti, 2 Nissan
Honda: 1 car, 1 minibike
BMW: 1 car
7 cars. 2 gm. 2 mopar. 3 mazda, but one is half gm....
Down to 6 cars right now but will include the ones recently sold as well.
Total cars - 10
Manufacturers - 5 (MG, Jensen, Pontiac, BMW, Lamborghini)
2 Toyota
1 BMW (MINI)
1 Mazda
1 GMC
1 Mopar (Fiat 500, and I love telling Dodge people it's a Mopar.)
3 cars, 2 manufacturers
BMW
MINI
Porsche
So what's the full trifecta? Just three cars that cover all-, rear- and front-wheel drive featuring four-, six- and eight-cylinder engines?
In reply to David S. Wallens :
I'm calling you out for being a cylinder bigot ;-) what ever happened to 10 & 12 cylinders?
5 cars, 2 manufacturers:
4 Porsches (718 Cayman, 986 2.7, 986 550 SE, Cayenne Turbo)
1 VW (Golf R)
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