Having an issue, where sometimes my indicator comes on when parked, sometimes when I lock or Unlock. But can flatten the battery if it comes on when parked. Think it is the near side

Sounds like a dodgy indicator / hazard relay unit.

 

It is behind the hazard light switch inside the car.

 

The indicators can't come on when the ignition is off, but the hazards can - so is probably this?

It could be a dodgy convenience unit as this controls the visual lock/unlock confirmation.  It may be an idea to get someone with VCDS to turn it off which will help pin point it as the cause.

I had exactly the same issue and flattened the battery on my first day of ownership! The near side indicators (all three of them) stayed on when I locked the car, but I didn't notice. Went to the car the next morning and battery was flat as a pancake. It's not done it recently though and I have no idea why, as I've not changed anything that could affect it. Give the hazard light switch some good finger action and it might sort it, as it did with mine. Cars are random.