An unservicability is just that, who are you too make a judgement over what another licensed engineer has snagged, who also will over see or oversign your extented check A when you will have no maintenance approval from the MO.
Your idea seems to be an extension of the CAM role and would very possibly cause a great deal of friction between the MO and its customer, the only benefit I can see is that you will earn yourself commision.
No doubt as mentioned earlier you will still expect to be paid even when your own findings agree with that of the MO and as for your out of hours trouble shotting! Well who is to say you've got it right in the middle of the night having just been woken up and not seeing exactly what is going on.
Who also is not to say that you will make the right decision as to repair, overhaul or replace items as required and that you can find a better deal than that already offered.
It seems a path littered with problems, you only need to get it wrong once and the word will spread like wildfire. Damaging what I assume to be a good reputation.