Bought a 98 1.8t Quattro with 140,000km off an insurance salvage auction. Only was hit in the passenger door and just needed a door shell. It leaks a bit of oil, its dripping off from where the oil drain plug is but not from the plug itself. Mostly everytime starting it up it will put out a lot of white smoke for 10-15 seconds. Car is extremely slow, no onset of boost or increase of power through the rpm range. Roughly 13-14 seconds 0-100km/h no strange engine noises. I'm thinking its a turbo seal, diverter valve, or that the white smoke is separate from the lack of power and is due to a cracked oil cooler.
Any advice on where to start? This is my first German made vehicle so I figured I'd check here before getting to into it.

Edit: No check engine lights either, oil level light was on when I received the car, topped it up and it went away. Will be doing a full fluid and filter change on the car.