Not so straight forward.
It is apples and oranges .. one is a Compact SUV, the other a compact Sedan, so the X Trail - better off road.
Fuel efficiency - C200 I would think, smaller wheels, less effort required to spin them.
Cheaper to maintain - hmmmm - not sure.. But they *may* be even.
Stability - Lower Centre of Gravity for the C200 means greater stability.
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Keep in mind that there's the C200 and C200 Kompressor, and for some years a C200 CDI (diesel).
Also the X Trail has 2L, 2.5L engines. and a 2.2 diesel as well as GT edition (whooping 276 bhp).
For CR-V vs X Trail - tons of comparisons online. Look especially for the Australian ones as they are probably most relevant to .ke