Guys!!

In need of some advice here. At present I have a 2001 Focus 2.0 Zetec Estate. I get around 280-300 miles to a tank of fuel. I have seen UK Spec Subaru 2.o Turbo's Estate (Wagon's I think they call them?) going for as little as £1,200 which has made me think about selling my Focus as a Scooby being a 200+ bhp 4 wheel driven car.....but, the think that is getting in the way is...... I drive fairly hard, I wonder how many miles I would get out of a tank and also are parts expensive?

Thanks in advance for any advice as I know nothing about Scooby's!