Anybody know anything about capital gains tax?

I sold my house last year. I had used it for B&B for 10 years. I was told to sell the house ';with B&B potential'; and not as a going concern to minimise CGT and now, my accountant has said that I will have to pay £904.20 by 31st January 2007. I closed the business a month before moving, so only sold it as a private dwelling. Is my accountant correct. UK only please.