Depends on how much of it is OEM and how much of it is aftermarket using flexi LED strips from amazon etc.
I know that the trim pieces with the red LED stripe in the door are OEM and based on the 8V prices they are around £130 each from Audi. Thats £600 straight away.
I personally won't fit any aftermarket LED strips to a customers car, I only deal with OEM parts trim wise. The LED strip along the dashboard - is that a part of the ambient lighting package? If so then it will be possible to buy the trim bits with the LED fitted from Audi, its a matter of getting hold of the part numbers and the prices for them but judging from the door strip prices I can't see them being cheap.
From the wiring side of things which is what I deal with 99% of the time its not too difficult, harness prices will vary dependant on complexity but wouldn't be any where as expensive as the parts.
There is also the question of whether the LED strips are RGB which allow the colour to be changed, this will require new modules and a lot more wiring, something that I am looking into with a company (
www.audiupgrades.co.uk) that I have teamed up with as there is a demand for the same type of ambient lighting on Q7's.
If you would like to discuss it further then I am happy to do so and look into it with a bit more detail, with the 8Y being so new getting information isn't the easiest but we have our ways and means.