Site with half built house - planning situation

We're interested in a site that's for sale. The site is a narrow strip of land from the road up a hill. It has a half built house close to the road (bottom of hill) on it and planning permission has just been renewed for it.

How do I go about finding out whether we could get planning for a house further up the hill (where the views are). Should we go to the planning office even though we don't have firm ideas about what we'd like? What information should I be able to provide?

We'd only be interested in buying it if we could either - change the planning on the house to add substantially more onto the house or to build another house at the top of the hill (with a view of either selling or renting out the original house when completed).

What could we expect from a meeting with the area planners? Can anyone request a meeting?

There's a reason the first house was being built at the bottom, you wouldn't (or shouldn't) be given planning permission to build at the top of a hill, better view for you but then your house is affecting everyone elses view of the hill

Have a look at the local county council website and you should be able to see the planning for the existing dwelling and what the conditions are that apply to it.