You will change all the 4 tyres every year plus fuel expenses every month plus maintainence/garage expenses for 7 years.
So your monthly expenses for a $20,000 car = $700/month (approx) and for $200,000 car = $4000/month (approx)
My numbers are for car that runs 10 miles everyday or 3650 miles a year.
Your numbers are grossly incorrect. If you're only putting 3650 miles a year on the car, you wouldn't expect to change the tires once over the 7 year period. Tires typically last around 50,000 miles, and for some reason you're assuming you change them every 3,600 miles. Next, 3650 miles in a year would not use nearly as much gas as you think. Let's assume your car gets a paltry 20 mpg, that would be 182.5 gallons per year at $3.50 per gallon would be just under $650 per year in fuel costs, or roughly $54 per month, and that's estimating things purposefully more adverse than they would probably be.
Next, if the car costs $20,000 over 7 years, that would be $2858 per year, which is $238 per month. So where you concluded that a car would cost $700/month, what we actually have is less than $300/month. What isn't accounted for is other general maintenance, but for how infrequently you're driving the car (less than 26,000 miles over 7 years), it's going to be pretty inconsequential.