im looking to buy this car

http://pistonheads.com/sales/816643.htm

Now its a 2001/Y reg 2.5 litre.

How does this, if at all, affect the new tax laws. Some say it will cost me £700 a year to tax, others say £400 a year, some say its too old and therefore will cost circa £200 ish. (the same rates for the last decade+).

Thankyou