Hi.Whilst the rules have yet to be written in detail and legislation enacted, it is probable that non-resident owners of UK property will only be charged to UK CGT on any increase in value from 6 April 2015 and not on any gain accrued up to 5 April 2015 so it is not going to be nearly as onerous as one might have initially thought.If you didn't disclose the gain you might be committing the criminal offence of tax evasion and if HMRC found out from all the databases that they have access to, they will pursue you through the courts in the country that you are living in and, if need be, your assets will be frozen by the local authorities. There is much co-operation between different tax jurisdictions these days.The £75K deposit is simply part of the cost of the property and that (the cost) long with expenses of purchase and sale and the cost of any improvements will be deducted from the sale proceeds to arrive at the gain. Having a charge put on the property to secure that loan will not reduce the gain as that would be double counting. All this will be academic if only the post 5 April 2015 increase in value is going to be taxed. You could reduce your potential exposure to CGT by putting the property into joint names with a spouse but you would need to consider what effect this would have on main residence relief and letting relief, if appropriate. Take a look at the HMRC helpsheet HS283 here for more information on the main residence and CGT.I hope this helps but let me know if you have any further questions.