Owning your own home

It had permission for a two story dwelling, though this expired last year. And it has access to all the aforementioned services. The only issue I am concerned about is that the land used to be someones double garage so it is very close to someone's property.

I have no knowledge except that gleaned from grand designs, but a couple of the builds they did built a fair bit underground, and piped light in through those tubes.
You could have a two/three story above ground, and a large cellar pad below.