Thanks Dave, yes that was all covered in the deeds and planning consent. The reason I wanted more info about surrounding landowners was to check how robust some of the agreements are. I'm sorry that I can't say any more at this stage and am being a bit cryptic, but I'm not wanting to give the location away!
There's nothing there that's causing me concern re the water, drainage or services though. I know it all needs checking to make sure it's still current but it seems good so far.