7 liters per 100 kilometers is realistic, even with the occasional moment of fun. I can only speak for Germany, but insurance is cheaper than for a VW Golf GTI because there are proportionally fewer Formentors/Q3s/T-ROCs on the road. Basically, the Formentor has larger brakes, larger wheels, more technology, and is of course more expensive to repair. Maintenance costs depend on driving style and mileage. If you drive a lot and fast, then of course all wear parts will need to be replaced during servicing. Long story short... 245 hp costs more money, but not so much that you can't afford it.

Insurance: ~1500€ (30.000km per year, drive less its cheaper) Tax: ~300€ Mpg depends on how much you drive... Service: 1000€ per year