I've never done this service myself, but with the many infos given here as well, big thanks to
@audifan, I've built up the courage and got the brake fluid change done!
Well, kind of.
So I've used Halfrauds 1-man kit, can't really ask anyone to help with this, and filled the brake reservoir to top, put some fluid in the empty container, connected the hose, loosened rear off-side nipple, I was worried it might brake/shear off as looked a bit oldy, but thankfully it turned without any issue, yay.
Then I got into the car, pressed the clutch slowly 2x and run to see the liquid in the tube. There was none.
What's the issue? Damn. I pressed clutch, not brake. I was a tad nervous.
I'd tried the brake pedal, this time I heard the system work. When I ran to see the liquid in the tube, it was there alright, BUT a tiny bubble slowly crawled back itself into the system! That's no good.
Could it have been due me pressing the clutch, with only the brake nipple open?
So I pressed the brake 3x, and quickly closed the nipple. I hope it got rid of the bubble :/
So I put the bits back and drove the car back and forth on the driveway a bit, to check the brake strengths and for leaks. All good, no squashiness, but still a bit worried about that bubble.
After having a look at the brake fluid, to my surprise it wasn't dirty at all. It looks green but see-through. I've been owning my A2 for 3 years, previous owner didn't mention he got it done either, so I would say been there 5 years maybe. It didn't look clean from the engine bay, (see pic, new fluid on top/old fluid on bottom), but looks rather clean in the tube (see other pic, I had to crop it a lot, as it didn't let me upload it otherwise).
I was kinda hoping it's gonna be dirty, mostly because the clutch is vibrating so much like a proper massage, also feels heavy compared to other cars, until depressed completely, that I wanted to see if the old brake/clutch fluid is the reason for it. But it's clean, at least not dark brown.
Shall I bleed all the nipples anyway, including clutch, or if O/S nipple has clean fluid, all should have the same? Thanks.