You will also be paying monthly fees to the letting agent + property and contents insurance + council tax. Plus, landlord insurance to cover your liability for tenant injury, emergency rehousing,eviction costs, etc.
In addition, there will be wear and tear on fittings (tenants are rarely as careful of LL's property) repairs to washing machine, replacing china, worn carpets , stained bedding etc.
You can deduct some of the paragraph above against the tax due on rental income (if you have to employ an accountant , add his cost)
This is not your main residence so when you sell the property, you could be liable for capital gains tax.
Rent is only payable for let and occupied periods. If a tenant leaves early, defaults, or you just have a gap between one leaving and the next moving in, there's no rent income. But you still have to cover insurance, CT, and possibly a minimal heating bill to prevent freezing protect water papes etc.
Getting rid of a tenant who went bad, can be time consuming and expensive and a gigantic headache.
You need to do a lot more sums and a lot more homework.
In your shoes, paying a mortgage which is a substantial proportion of the monthly income, I doubt the net rent will provide a worthwhile income. A substantial high in mortage interest rates ( highly likely in near future) would erode rent income even more and you should not rely on a rent rise to cover it. IF property values rise, you might see it as a longterm investment when you eventually sell ( but potentially liable to Capital Gains tax).
You also need to fully educate yourself about Landlord responsibility and liability. In Scotland, all private LL's must be registered and approved by their local council. and it's possible other parts of the UK may follow suit in future.