Is your specialist using Star? If not then I think you are being charged far too much. If you have an Android mobile 'phone then loom on Amazon, eBay etc for an ELM357 Bluetooth OBD2 device, they are around £6 -10 and download an App called Torque from the Google Play store (about £2).
This is very flexible, can offer customised readouts and gives a lot of information on many different parameters but be aware that not all manufactures give the same data via OBD 2 and as I said, your diesel may not be ffully compliant