Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
Pleas advise the total site area occupied by your property and garden. Once I know this I will be in a position to assist you further.
Provided that plot is below half a hectare. and a quarter of an acre is well below this, any sales of all or part of the plot would attract Private Residence Relief (PRR). PRR relieves Capital Gains Tax (CGT) at 100% so thre would be no CGT to pay.
I do hope that you have found my reply of assistance.
Have a look at HMRC Helpsheet 283 which you can find here:
You will need a wet towel round your bead and the backs of lots of used envelopes to assist!
I would not worry though as your overall plot is within the 'permitted area.'
Delighted to have been of assistance.
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