Wow - Lee, You're NOT gonna like this : From what I can see, It's really not too hard, but man the driver-struts are way expensive. Here's what I can find that seems to differ.
Driver- Struts : 8U0827851 - you need 2, they're not handed - $680 each
Boot Lid harness : 8U0971148BM - $380 - but you MAY be able to get a way without this.
Switch in Boot Lid trim : 4G0959831B - price on request - which usually means it's not available - but this shouldn't be really expensive, perhaps $75
Control Module for Liftgate : 8U0959107 - $451
Bracket for above : 8U0907455 - $16
Total : $2282 - right now about £1513 -

I swear, NO tricks -:nerd: - this is whacked -
You should be able to get a discount from your Audi dealer, usually 10-15%, so that could help, but I am really surprised at both the driver-strut prices and the wiring harness price...
Here's the module scan from my car ...
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Address 6D: Trunk Elect. (----) Labels: None
Part No SW: 8U0 959 107 HW: 8U0 959 107
Component: HDSG-Modul H01 0549
Revision: 15001001 Serial number: 269400890
Coding: 183307C122
Shop #: WSC 00049 770 00188
ASAM Dataset: EV_HDSGAU316 001001
ROD: EV_HDSGAU316.rod
VCID: 7CFCE772F799C0C1333-8029
No fault code found.
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