Hi S0787571,
Thank you for your questions.
o agree an unequal share of beneficial income from property you need to complete a Form 17. (see .GOV .Uk).
Declare beneficial interests in joint property and income
Expenses arising in the income from property business must be wholly and exclusively incurred.
Again more guidance is available online via the .gov website (property income toolkit).
Property rental toolkit
If you both receive an income from property in excess of £2500 that would meet the criteria for a tax return.
If you are not a receipient of Income from property then no return is required for you.
Thank you.