I live right next door to a Magikarp nest, and have evolved 5 Magikarp into Gyarados myself.

I can either farm 400 candy and allow you to evolve at your leisure, or I can farm the candy and evolve the Highest CP one that I find.

The cost for this service will be 500 FG, and whilst I'm doing this I will be grabbing every pokestop I walk by. My typical route for Magikarp brings me by 18 PokeStops per lap.

There are no rules posted on PokemonGO, so I am assuming this is a legal service.
If it is not please feel free to lock and let me know what is/is not allowed with PokemonGO