Use this oil, http://www.ebay.co.uk/itm/Quantum-Longlife-3-5W-30-Fully-Synthetic-Engine-Oil-5-Litre-Bottle-/131453080952?hash=item1e9b36d578:g:NSAAAOSweW5VAFXT
And these plugs http://www.ebay.co.uk/itm/NGK33-Spark-Plug-x4-PFR6Q-Audi-Seat-Skoda-Volkswagon-BNIB-/131992293488?hash=item1ebb5a9070:g:Yw8AAOSwx2dYG2pe
And this oil filter http://www.ebay.co.uk/itm/Mann-Oil-Filter-Spin-On-Type-Audi-A4-1-8-T-Quattro-Performance-Service-Engine-/231318345475?hash=item35dba5d703:g:aekAAOSwVFlT~mo5
I wouldn't use a flush, as long as you do regular oil changes circa 5000 miles it should be okay, does it have good service history and have you ever had LOW OIL PRESSURE warning?
Hope this helps, I've had experience with 1.8t engines for over 10 years so any questions just ask.