I've narrowed my cars down from maybe 15 at an all time high, to only 10 now but going any lower presents problems.
Take it in categories.
I need a people mover and parts chaser that my wife is safe driving. A minivan suits that need. I don't care much which one, but own a GM currently as the price was right. If we ever replace it, I'll just get another anonymous minivan (the thought on this one was that if it ever died, the engine would fit two of the other sports cars).
I want to have a grand touring car or two. My Jensen Interceptor is ideal - reliable, smooth, relaxed tourer with reasonable power. But I wouldn't want to get rid of the stablemate, the much rarer and quirkier CV-8. Almost 700 lbs. lighter, with fibreglass body, and the same big block Chrysler (in this case with sixpack, while the Interceptor makes do on a single 4 bbl). Very fast, not nearly as refined, but when you boot it and the secondaries open at 100 mph, I'd miss that feeling if I sold it.
And I have heard that one needs to own an Italian grand tourer at least once in a life time. I'd have a really hard time parting with my Lambo Islero S, especially given the total production of only 100 cars, as I'd never be able to find another one if I relented. It offers a different grand touring experience than the torquey Jensens do.
So have to keep two Jensens and the Islero.
Classic sports cars. I have always owned MGs. I suppose I could possibly sell my MGA Twin Cam race car - I haven't foudn time to run it for the last few years, and I still have an MGA Deluxe (4 wheel disc) coupe for the street experience, and an even better touring car, the MGC, tuned to 175 bhp. So maybe I could sell the race car and keep the MGC and MGA. But then there is the Jamaican bodied 1956 MGA with modern (3.4 GM) engine that is a lot of fun to drive in the summer and doesn't bake your brains. Have to hang onto that a few years longer - it took me 3 years of effort to build it the way I wanted it and I sure didn't do that for anyone but me. So one Jamaican, an MGC and an MGA have to stay.
Modern sports cars - had a lot of fun with the 1988 Fiero, optimizing the chassis and refining a larger displacement turbo installation. A real sleeper I've owned for 20 years. Guess I can part with it after all those years as I have a replacement in hand, a Solstice GXP coupe with an engine tuned to about 350 bhp, which is even faster than the Fiero.
So my minimum seems to be one parts chaser, 3 vintage grand tourers, 3 vintage sprts cars, and one modern sports car, for a total of 8 cars. Too bad I only have a one car garage.....
I have of course sworn never to buy another car. As it was only about the 10th time I've done that, it might even be true this time!