When you have a Buy To Let mortgage the loan to value at the moment is a lot higher so if you remortgaged you may not have enough equity.
But a few years ago I was in a position where I was was on a repayment mortgage and had to let out the property instead of living in it. I contacted the mortgage company and they agreed that I could continue with the same mortgage. Also if you have a BTL property you are responsible for the buildings insurance and you have to take out Landlords Insurance.
BTL mortgages usually carry a higher rate of interest due to nature of them as they are classed as businesses
My advice would be speak to your mortgage company. You will also need to know how much you could potentially earn in rent. I have a property that I rent out at the moment and this is with a Property Management Company. They do all the work in collecting rent, repairs, finding and vetting new tenants all contracts etc. They charge a percentage of the rent for doing this. I feel it is worth it as I lived distance away and I do not want to be bothered by the tenant if say the tap drips and it needs repairing. Also the property management charge is also tax deducted as you have to pay tax on any profit you make from renting a property.
Hope this helps
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