from what i can tell, you only need it to be "fixed" by a tech eg SP if you actually do something wrong to it ie overpressurising it might blow the solenoid, so that would be a professional fix, not a DIY effort.
similarly if you attack the circuit boards then you would have to buy a replacement from SP
but stuff like changing hoses or banjo fittings, and servicing the orings/lubing/general care is a 5 minute job and can easily be done yourself. just make sure you have all the correct bits (ie buy a spares kit, £15 ish from planet)