If, as seems likely, you'll be operating a Rotax four stroke, the manufacturers preferred choice of fuel for their engines is Mogas. Avgas can also be used without any mixing problems.
I operated two aircraft very similar to a Eurofox. The operating costs amortized and including fuel, servicing, insurance, parking but not hangarage equated to approximately £45 to £50 per hour on 50 hours flown.