Looking at buying a Superb (66 plate onwards)

At first i was undecided wheter to buy a secondhand Octavia or Superb, then saw that theres much more Options availible on the Superbs, my question here is what are the things to check when going to look at the car??

Im looking at 2L Diesel (as ive read that the 1.6L DSG can have problems)

one of the cars i hope to see at the weekend is a 2016 (66) 2L L&K DSG hatchback KESSY Xenon lights

but as ive never owned a DSG i dont know how to check it

ive read that it may be possible to request info on the car from TPS is that still possible ( from just the reg)

ive got VCDS and (if the dealer allows) may be able to get a scan

but if not what is best to check??

im not sure if the car requires adblue, if so is there any special things to check for

where is the build sticker located on the car? in my previous Passats & my Exeo its in the boot/spare wheel area

Thanks in advance