I do not think the A2 has been available for some time. The price for the BS9000 is clearly the price a new one would cost now rather than the 2001 price which was nearer £2500.
On the value of the A2; the price it is worth is clearly what the market will pay - I wouldn't pay £400 for one but that is because I don't like it! I will be paying a considearble amount to have my Beolab 5000 refurbished - many people would regard this as a waste of money - it all depends on what you want!