Ok, I separate regular maintenance (oil changes, brakes, tyres) from the equation.  I would still argue that wear and tear repairs like struts, wheel bearings, etc that cost less than $2k-$3k a year is preferable/cheaper than on-going monthly payments of $322 on a Toyota Yaris, even if it is a new one every 4 years.  Once your yearly repair costs exceed ~$3k (threshold obviously depends on the value of cars you buy.  An Audi S5 has monthly payments of $706 so my threshold on that would be $5k-$6k), then I'd consider retiring the ride...