Buy-to-let is when a buyer purchases a property specifically to let out to tenants thus gaining a regular monthly rental income from the property.

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Not only does this give investors an opportunity to make a profit from rental income it also gives investors the possibility of gaining equity on the property if the house value increases. The right investment could give you a return of up to 10% gross per annum.
Buy-to-let mortgages require a higher a deposit usually at about 25% of the property value also you will need to show the lender that rental income will cover the interest payments by at least 125%. This is due to the risk factors of the property being unoccupied for a period of time and the cost of property maintenance.