Very easy to do yourself. My tool of choice is a SensorKlear from LensPen. I bought several from (IIRC) 7dayshop a few years ago and still have a couple left - I treat them as a single use item for sensor cleaning then relegate them to lens/filter duties or rear screen/phone/specs. I've tried one of the wet cleaning systems and managed to smear the oil droplets all over the sensor, giving me the impression that I had scratched the low pass filter. A later clean with the SensorKlear disposed of the smears instantly. (Phew!!!)