hmmmn , well I've tried to quit, or at least lessen the financial outlay, probably every year for the last 10 or so. After i "learned" about being debt-free/ FIRE. Probably spent up to a 1/3 of annual take home $$ on vehicles - and speed/ handling upgrades - insurance, etc. for many many years.
Some cars i broke even on, some sold for a profit, some lost $$ on. Never really had to worry about a car breaking down as there was another to drive if needed, and it geared me towards being my own mechanic, so 'saved' a bunch of money in that sense.
But to get the future cars i was lusting after [ mostly used muscle or sports cars ] I needed to churn thru the others to raise funds , costing $$ in taxes and registrations all the time. It was like having several mates, that clamored for attention, fun and intoxicating at first as you experienced them for yourself [ as opposed to just seeing / sitting in one ] - but i could move on, by selling, and moving onto the next desire. Part of the lure was the thrill of the chase, finding a low milage survivor. Some cars just "look the business", and there was an appeal of aesthetics / architecture / functionality thrown into the mix.
But that all sort of crashed when i sold a super low mile, 80's Mitsubishi Turbo, that was originally bought by a 70 yr old couple. I got into a funk where i convinced myself i needed to sell it, for the $$ as well as to pare down the collection. That car had a "welcome chime" when you opened the doors, "la-la-la-la, hm, hm , lum-dee-dee-dee" . And my approx 6 yr old kid fit great in the backseats. She was Crying when i announced i had sold it thru E-bay to head 1/2way across the country to another marque enthusiast. Later that day, i went out to the garage and wept, thinking of my kids disappointment, and that i really didn't need to sell it for the $$ i recieved, and that i was an idiot 'cause of this hobby.
So since then, anything i buy, i intend to keep for a long time.
Two of my new cars were "special order" built exactly how i wanted them, colors , certain options, etc. - Both are "headturners", not your typical family sedans. It's nice when a bus-load of kids sees the cars and get excited and gives thumbs up. Or a kid points excitedly in the gas station - "Daddy thats Batmans car ! " . On those vehicles I feel almost as if i commisioned a piece of art to be created. Without my involvment, they wouldn't exist on planet earth. They'll be passed onto my kid , if she wants them, which of course currently she does. Although there is a feeling of trepidation that my car habits could influence her to go down the same rabbit hole i did.
So now i try to temper the time, effort , and $$ spent - along with more varied pursuits - camping, martial arts, gardening, etc, so that we are living a "fuller" life. Still there is somethng great about rowing thru a manual gearbox while i feel the G-forces, in a fast, well handling car....
Sold the car-trailer this year , as just owning a trailer, aided and abbeted searching for other vehicles on craigslist.