V happy for you (and jealous of you for having a great car...sold my JTDm and I am gutted - wish I hadn't and I am now looking at getting another GT if my current car sells)!
Anyway, I had a similar experience but walked away from a GT being sold by a non alfa dealer/specialist - I bought privately and it was all good.
The trader in question assured me that the car was in great condition and offered to do the belt - i declined and said I wanted some money taken off so as to meet me half way - this was prior to seeing the car - they agreed. When I arrived, the car was not the best and they really tried the hard sell n- they were really pushy and got really Sh....I mean annoyed when I turned it down. After buying my GT privately, I swore to save up lump sums, sell my current car privately and only buy privately - it is harder work but worth it for the lack of hassle in the long run, honestly, it was a truly horrendous experience - I am not really the sensitive type but the way these places make you feel!
I wish I'd have gone back to the garage the following week when I'd found the car for me - bunch of *!"£$%^.