I did based it on two people and I'd check the accommodation as sometimes you may end up paying the same price for a single person in a double room. If you don't mind hostels you may get better deals.
Usually these prices are for a pair, but try the above links by putting one person and check what prices comes up? Let us know... I would be interested. £200 for a week is a bargain esp in summer time
Can you book for just one person at £199.99 or does it have to be for 2 people at £399.99? (y)
Wow now this is tempting
Budapest and Prague were really good, weather is good at that time of the year too