What would you do about this car situation?

If your only driving 26 miles a day fuel mileage shouldn't be an issue. You ain't gonna notice a difference. And with 78,000 miles. That car ain't even broke in.$600 for a tune up, they saw you coming. Tires and brakes you'll have to replace on any car. I'd say keep the car stay outta debt. It's sounds like your a city driver so a corrola is only gonna get about 25 mpg. If you want a payment use a credit card to fix your current car.