Many thanks for the first response.
The shed does not form part of an existing farm but simply appears to have been a building for cows in the winter. There are remnants of fence wiring and other items in surrounding area so I will investigate further. I I have confirmed during my site visit that the tap in the picture actually has running water although it may not be suitable for domestic usage. Regarding the electric, you can see a NIE pole but again I take your thoughts on this as something to consider. Drainage is always a big issue and although a septic tank has been indicated on the plans, I understand this means nothing unless, as you correctly state, you have no land in which to drain to, even if a sewage treatment plant is installed.