Hi Reece,
I rent one of my houses and the best way to keep mr brown of the profit you make is to not make a profit.

sounds daft but you can take what would normally be taxed income into a tax free benefit.

My tenant pays ?600p/m so I make sure my mortgage repayments match or go over that amount bye a few quid. either pay off your mortgage quicker or borrow on the property you let so they payments go over what the rent is and invest it in your own house. that way it becomes a tax free benefit as your personal mortgage is lower.

but yes... renting a house is classed as a business so its a taxable income.. if you make any

hope this helps.
Thank you
Gregory