Hi,
It is possible that you will be subject to capital gains when you dispose of the property. Capital gains is the disposal value, minus buying and selling costs (including purchase price). As this is not your main residence, you will not be entitiled to private residence relief.
General maintenance, such as, replacement boiler, roof, windows etc, are considered revenue expenses and cannot be set against any gains.
CG15150P - Capital Gains manual: introduction and computation: computation: expenditure
Thank you.