So many points of view.
I do see Fox's point of view but the kid has a tuned Focus ST at the moment, about 250bhp so spending £18k on an S3 would be a massive waste IMO. He wants to take a big step up from hot hatches into something really impressive and serious.
Yes a big part of it is image but at 22 who isn't worried about that. At the end of the day the image is important but 90% of people won't know the difference between a Boxster and a 911. They will see the Porsche badge on both cars and know he is doing well.
I don't know the ins and outs of his finances but from what he has said he's on 32k basic and depending on overtime can pocket an extra £200-£500 a month. From what I can tell thought your looking at 90% of this being his to spend on what he wants, save, drink, holidays, cars etc... He actually spends most of his time at his girlfriends house so it's not like he lives at home with mummy. Secure job with potential for promotion.
I actually thought £1600 for a 911 was good for insurance.
He's not set on a 911, or a Boxster S. He' set on a very fast, very flashy, very good car that he can afford and can afford to run. If you don't know a 911 or Boxster is the answer then what?