Iam64 and Anya - the point is- if you specifically choose a house with a totally private garden and a paddock next door- with a covenant preventing building on it- and the covenant does not hold ( too old and not the original owners) and they build a house not 6' from your hedge- is it fair to be then told to cut down the NOT Leylandii, but mixed hedge?
The people who bought the bungalow with their kitchen window and door 5' from our fence and mixed hedge- bought it because it was quite a bit cheaper than the others exactly the same. The tress were there the day they first saw the house, on their second visit, on the day they signed the contract and the day they moved in...
They went on and on about it- 10 page letters without punctuation! We did cut the height down, but it made no difference of course as they were so close. They went on and on about the eldrberries staining their patio too- and one day phoned to say I had to go over and pick 'our' slugs from the patio. How do you know they are mine, I asked? Well you are the one with the big garden, they are bound to be yours, was her reply!
Very different to a hedge being planted after people moved in and not maintained.
If you buy a house with little light- cheap for that reason.... then ....
As said, the builders specifically didn't build at the bottom of our garden where the leylandii hedge was, as they knew it would be impossible to sell- and put the pavement ad access road there - as it was a small development, that was no trouble to us at all.