https://help.gosimpletax.com/hc/en-gb/articles/360000901730-Estate-Income-Restricted-Finance-costs
For the tax year 6 April 2018 to 5 April 2019,the allowable costs of getting a loan or alternativefinance to buy a residential property that is let,and any interest on those loans and alternativefinance, is restricted to 50% of these costs for each property business.
To show the 50% finance costs on the SA107
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Select Residential Property Income
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