Hi, thank you for your question. As the property is a buy-to-let property you will not be able to use your PRR exemption as this is limited only to your main home which you occupy. However, if you had ever occupied the BTL property as your main home then you would be entitled to some reduction to your CGT bill.
If this is not the case then you would be liable for CGT on the increase in value (£54,950) and your liability as it was disposed of in 2015/16 should be £11,199.50.
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