OP, you asked in the wrong place, you would be better off asking in Property.
There is a high demand for rental property at the moment, so it would not be a daft decision and property should always increase in value bar a few exceptions.
You need to look at the overall picture. You would get the rent each month, less agents fees if you use one. You need proper Landlords insurance and the property must have EPC and electrical certificate and smoke alarms and carbon monoxide detectors. If you don't use an agent then you will need to protect the deposit yourself.
I would use an agent certainly to find a tenant and do all the proper checks and credit referencing etc even if you don't want to use one ongoing.
You will need to do a tax return to declare the income. Interest can't be set against the rent any more, but you can claim a tax credit of 20% if you have paid tax elsewhere, and you need to factor in tax that might be due, plus accountancy fees (shop around). I would have the rents paid into a separate bank account and pay all expenses out of it and then leave the balance to cover tax and repairs. You will also need to pay utilities if the property is empty between tenants.
You are also responsible for all repairs and maintenance so if the cooker breaks down you repair/buy a new one etc.
You will need to pay stamp duty on the purchase as you already own a house.
and be aware that interest rates are only going to go one way which is up, so fix your rate for as long as you can, and consider whether it is still affordable if the rate goes up.
Have a look on local estate agents websites for fees, or ring round a few and ask what their fees and commissions are, how often they do inspections etc.