I'm only 19, got my Omega 2.2 when I was 18. Just sold it. Make sure he checks insurance, I started paying £340 per month, then after 5 months switched to elephant where I then paid £192 per month. That was the best possible quote, I couldn't beat it and I tried for many many hours. So make sure he checks insurance carefully, because buying a £700 2.0 could cost up to £2000. And being a student is one of the worst risk factors, if he were to be let's say...an antique dealer he'd get a better quote.
Jesus christ. I was insuring a 2.0 16v Saab 9000 when I was 19, for £70 a month. I'd have expected an 8v Omega to be much less, as it is seriously underpowered.
The most I paid was £152 a month, when I was 18, on a 1.4 16v hatchback. That was stretching it...£340 a month is the sort of quote they give you to make you go away!