Deliberate mistake: In Series 1 episode 1 Nick can use a laptop fluently, yet in series 1 episode 2, Nick has to ask where the "." button is.
Revealing mistake: At the end, when Nick is painting a nude picture of himself, he moves the mirror and even at a quick glance you can see he has boxers on.
Visible crew/equipment: Just as Ben starts to sing about life, there is a shot of a picture on the piano. If you look at the picture, not Ben, you will see the reflection of a camera or microphone arm.
Plot hole: Janey is on the phone trying to win concert tickets and says, "She has to be caller number 5, rules of the contest are very strict." Susan then says something else and Janey says on the phone, "Dee I have to go, mum's going mad again." She evidently isn't on the phone to win tickets.
Answer: Easy. He could have got the guitar at any point in his life. As for keeping it in the attic? You're not going to throw out a £1000 guitar any time soon.
Ssiscool ★