I've just acquired a used Sportback with very low miles (9k) from a main Audi dealer. The car is just under 3 years old and while it doesn't seem to have received much body care, it looks to be free of obvious swirl marks and scratches. I used to enjoy car detailing, but I've just done basic washing and waxing in recent years - the A3 is my first used car for some time, which means that most of my cleaning products date from about 2003-4! I spent a few hours inspecting and cleaning the car today. The main issues I could see were slight tar build-up around the arches and a generally rough feel to the paint (Garnet Red metallic). The dealer also appears to have prepared the bodywork with a very strong wax - more on that later. After a quick wash, I used Autoglym tar remover as required, rinsed, and then hand-applied Meguiars Deep Crystal Step 1 on most of the panels. This got rid of the tar, but didn't leave an especially smooth finish. I've read that I should probably use a clay bar, but I didn't have one to hand! I then proceed to apply Meguiars Deep Crystal Step 2 and finally Autoglym Extra Gloss Protection to most panels. The results are ok - but there's definitely still a slight roughness to the panels when felt by hand. However, even in good light, I can't see any obvious contamination, swirling or fine scratches. I was just wondering if the dealer's own wax could be a factor here? It looks like it's spotted over some of the window glass and almost feels like a tree sap!