Sandero 1.2 eco2 or 1.6 MPI?

Hi, you’re about to get me a sandero, mainly urban + overland. Would like to get out as cheap as possible in the maintenance, therefore the question: How much does the tax and consumption difference between gasoline 1.2 eco2 (new car) and 1.6 MPI (used car) make up? The bigger swallows already more fuel, right? Thanks already in advance, mfg