Hello, I am Keith, one of the experts on Just Answer, and pleased to be bale to help you with your question.
Could you please expand a tad on your question? Normally it is the net gain which would be exposed to Capital Gains Tax (CGT) on disposal.
As a general rule the gain is calculated and taxed on the whole transaction as at the first date of sale. Thus you pay CGT in advance of some receipts. In the event of a shortfall in the sales receipts you can apply to HMRC for a refund.
However, you can apply to HMRC for the gain to be treated in installments, but the period of such installments may not exceed eight years.
Thank you for your excellent support.