Jolan, where are you?
I don't care for hedges; what I call my hedgerow is more like a strip of jungle. I still tend the hedges on my mother's property, however; there's an 8-ft. hemlock one and and a 12-ft.(!) spruce one, along the frontage. To trim the latter I simply lean an extension ladder against the hedge itself (that's how dense it is)- not very safe but I'm not about to set up scaffolding. I looked up Leylandii and found this fascinating bit:
The Cypress's rapid growth (up to a metre per year), great potential height, often over 20 metres (66 ft) tall in garden conditions, they can reach at least 35 metres (115 ft), and consequent heavy shade which results in their capacity to cut out light, can make them a problem. In 2005 in the United Kingdom, an estimated 17,000 people were at loggerheads over high hedges, which led to violence and in at least one case murder, when in 2001, retired Environment Agency officer Llandis Burdon, 57, was shot dead after an alleged dispute over a leylandii hedge in Talybont-on-Usk, Powys.[12]
Part VIII of the Anti-Social Behaviour Act 2003 introduced in 2005 - also known as the “leylandii law”[12] - gave a way for people affected by high hedges (usually, but not necessarily, of leylandii) to ask their local authority to investigate complaints about the hedges, and gave the authorities power to have the hedges reduced in height.[14] In May 2008, UK resident Christine Wright won a 24 year legal battle to have her neighbour's Leylandii trees cut down for blocking sunlight to her garden.