Hi all. thought I'd share a recent experience in case anyone else faces a similar issue. Not long ago, whilst driving along the great ocean road (3 hours from Melbourne), I started getting weird electrical issues, firstly the radio volume disappeared, then random error messages, and eventually the car dropped into neutral and I lost all steering. Eventually figured out the battery was flat because the alternator had failed. Being in a remote location, no one had a battery and no one had an alternator and I ended up finding a local wrecker to replace mine and it it only took 2 days to get mobile again. They used a 15 year old one out of a Q5 Audi, so not sure how long it will last!
I discovered a few things:
1. If your alternator dies, you can drive for about 2 hours on a fully charged battery, with all electrics off, before the car completely stops again
2. The VW AU$1700 alternator is about $600 from an auto electrician if you can give them the right part number
3. The pulley on the alternator is a consumable part that is rated for 40-60,000km. The right person with the right tools can replace it on the car for about $100 and 2 hours labour. Removing and replacing the complete alternator is about 4-5 hours otherwise.
4. If you are going to charge your battery while it is in the car, don't connect to the negative terminal, use the body attachment point instead (the negative terminal has a cover over it, I think for that reason).
EDIT - noting point 3 - most alternators are still good even if the battery isn't charging, not many people know (even dealers) the pulley is a consumable part and can be replaced without taking the alternator out, by taking off a panel in the wheel well. The one needed for a Golf Mk7 R with Bosch alternator is a Litens 920851A. You can confirm it is broken if it turns in both directions, the design allows it to turn in one direction only when working correctly.