[Ropster]

I am considering getting a greenhouse for my garden and wonder the best place to put it

does it need to be in full sun ? my garden is south facing and the (unheated) conservatory on the back of the house gets so hot only very heat hardy plants survive in it

the most convinient site is against the back hedge which will mean it is overshadowed for a lot of the day

any advice appreciated, I dont want to move things around to get it in full sun only to find things get fried and it is unusable

[tode]

I've got a similar prob: lean-to GH on South wall: gets really hot in Summer.
But I think the most important factor is the condition in Winter and early Spring: you need plenty of sun to keep it frost-free and get things off to an early start. You can do so much more, even if it's only frost-free.
Then sort out a solution for shading in Summer.

[pushrod]

any advice appreciated, I dont want to move things around to get it in full sun only to find things get fried and it is unusable

You can always shade it  - you can't move the sun
Make sure you get one one with automatic vents in the roof and louvres at the bottom.
 East west for the ridge is common. Quite by accident i ended up with the door to a fence - has turned out very useful though as it stops things blowing in when the door is open in summer.

[stickywicket]

I bought some green netting type stuff that you can hang up to provide shade and stops things from getting scorched.

[plum crumble]

the green netting stuff is really very good..........unfortunately I no longer need it as my neighbour has built an extension which has plunged my greenhouse into 100% shade. GRR I am having to resite it completely - which ain't a quick job for a 6x6 glass one.