Best large/wide hedges

Hi there, i have a really large back garden, which unfortunatly backs onto a small carpark and a patch used for kids to play on and cut through to the other side of the street, my fence is a standard council size at 3.5 foot tall, i got a quote for new fence and was told it would be 11 panels at ??1000. I simply cant afford this, so i am wanting to put a variety of bushes and trees along the back to make it more private, my greenhouse and shed is in full view at the moment, i have 6 fruit trees in the garden in and around the veg patch but need the edge made private, i currently have a twisted willow in the corner of the garden, but i could fit another 4-5 big bushes or trees there, obv not too tall, the limit is 8 foot. Any suggestions please?

Hawthorn.  Plant as single stemmed, bare rooted whips in autumn in well prepared holes or a trench.  Prune back to about a foot high and leave to grow a good root system over winter.  It will put on 5 to 6 feet during the next growing season.  Cut back the leaders to make the plants bush out and in following years keep trimmed to a height and width that suits your needs.

Hawthorn is thorny so will deter unwanetd visitors, provides blossom and nectar in spring for both birds and beneficial insects, plus shelter for birds to perch and even nest when its mature and berries in autumn.  Excellent plant and cheap too.