Hi,
The following guidance covers expenses incurred before a rental business begins.
PIM2505 - Beginning and end of a rental business: commencement
It must meet special rules to qualify as an expense and be incurred wholly and exclusively for the purpose of the rental business. If you lived in the property as your main residence and had private use of this whilst carrying out maintenance, relief would not be due under these special rules. Your expenditure on rent would not be incurred wholly and exclusively for the purposes of your rental business as it was incurred to provide you with a home. Relief would be due under the ordinary rental business rules for periods after the property was let commercially.
Thank you.