Thanks for your responses
You are making this far too complicated, which will lead HMRC to argue that you are drawing from your own capital to remit into the UK thereby creating a tax liability (inspite of how short a time this money remains in the UK and for what purpose its for and that your father in law is involved in the new house purchase)
Whether the money is loaned to you directly (or to your father) just make sure that appropriate paperwork is drawn up stating how much has been loaned, and what terms for the repayment (I,e by when and with or without interest) and how it will be repaid (from the sale of father in laws property)
Also make sure this money is remitted to the UK directly from your friend, and just alert your UK bank account of its expected arrival, as they will need to carry out checks on the money arriving into the UK (so the paperwork detailing the short term loan letter will back up the position)
1) You will keep the bank happy, with their laws and checks on large sums coming into the UK
2) Remain free of tax on this loan, as these are not liable to tax
30 provide the full information of why this money is coming into the UK and not implicate you with your own capital, which currently is not liable to UK tax under the remittance basis.
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