Faults:
What hasn't gone wrong would be a better question;
Reverse camera failed.
Sat nav failed.
Clutch gave up (expensive).
Injector problems, very expensive for just one injector replacement.
Clogged DPF replaced, expensive, even after a "Re-Gen" would not clear it.
A/C dead.
Various suspension and brake work, most of which could come under wear and tear, but some was very expensive.
There is more but too much to list. Interior also has serious wear, the car looked great when I bought it, but now looks like a 25 year old car, not a 12 year old one. Leather is all torn. For any nay sayers, the car was bought from a well known good dealer, very low mileage for its age, good condition and full history. I kept the car looked after and serviced on time, drove very very carefully, but it still went to pieces. And I have had many older higher mileage cars than this and they have all been fine, but not this car.
General Comments:
Avoid modern SUV/MPV/Crossover type vehicles. They are rubbish. Big, boring, bland and the diesels are unreliable. Not exclusive to this Qashqai to be fair, a lot are like this.
Like many people I bought it because it was spacious and popular (never buy something just because it is popular - lesson learned) and on the plus side it drove OK, was economical when running correctly, and well equipped and comfortable. But I cannot wait to sell mine soon and get something more reliable. After a few years and barely 20,000 miles, this car has cost me more than double on repairs and general running costs than any car I have had before!