Look at the surface of your gutter (a ladder may be required). Are there any cracks in the surface? This can lead to water leakage then in turn can lead to exterior damage of the property.
Are you gutters painted? If so a good way to measure whether they need replacing is to see whether the paint is flaking or peeling?
Peter E Smith can install an efficient guttering and fascia system to your roof, removing any possibility of future damage to the side of your building due to untamed rain water.