Hello and welcome to the site. Thank you for requesting I help you for your question.
My questions are as follows:-
1 Am I correct in thinking that the most cost effective way of me realizing the value of the Sandwich house without paying a large amount in CGT would for me to sell it whilst I am still non resident? i.e. paying CGT only on the gain made from the beginning of the 2015-16 tax year to the sale date?
If you were to sell the property before 5 Apr 2015 then you would escape CGT as you would qualify as a non-resident in UK for UK tax purposes.
If the sale took place after 5 Apr 2015 then your exposure to CGT would be the difference between valuation at 5 Apr 2015 and final sale proceeds. You would still be able to avail your gains allowance in the year of sale being a UK citizen and the gain would be net of costs
2 Do I have to stay non resident for the whole of the 2015-2016 tax year to benefit from this or just until the sale date/
The starting point is 6 Apr 2015 and provided you sell the property whilst still a non-resident then the gain is between 6 Apr 2015 and date of sale and you don't have to be non-resident for the whole tax year.
3 Can I sell two houses simultaneously on the same basis?
Each house sale is independent of each other and you could sell two houses simultaneously on the same basis.
I hope this is helpful and answers your question.
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