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.
A Very Brief Encounter - S9-E3
Plot hole: In season 9 episode 3, "A Very Brief Encounter", Ben is upset when he learns that Susan named Nick, Janey and Michael after lovers she had in university. But in season 4 episode 6, "Deliverance", there was a flashback of Nick's birth and we learned that it was Ben who named the baby. He heard someone say the word "nickname" in the delivery room and named his son after that.
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 ★