This is completely dependent on your circumstances and is a common conundrum for landlords. If you let the property unfurnished, you may want to consider purchasing a few items should the right tenants request it. You may also want to 'dress' the property for photography. Adverts with photos of a furnished property often receive a better response than unfurnished from our own research. Be prepared that if you offer the flat fully furnished and suitable tenants already have their own furniture you may need to pay for storage costs.