Hello, I am Keith, one of the experts on Just Answer, and pleased to be able to help you with your question.
Yes, you will, you should warn off your tax office of your new venture. Of course, with a net income of under the Personal Allowance of 11K for the 16/17 tax year, you still will not have any Income Tax (IT) liability although there may be some Class 2 National Insurance (NI) to pay as the income is over GBP 5966. Your statement when you self assess will tell you of any liability in this matter. However paying NI is complicated if you run a business involving land or property which is part of your activities. I would be inclined to draw your tax office's attention to the position when you advise them of your new landlord's activities (see above) and see how HMRC would like the matter handled.
I do hope that you have found my reply of some assistance.
There would indeed, always bear in mind Benjamin Franklin's dictum that in life there are but two certainties, death and taxes, although in his time NI did not exist!
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