If I get
Wanjy right, you want
factors to be considered.
This is not easy on the face of it because you've left out so many details. E.g do you already have a site in mind? Some plots sizes can only fit a 3 bedroom house if its a maisonette.
But the best starting point is with an architect. Peruse many architectural designs in the web and form an idea in the mind of what you would want, the discuss with an architect.
Other issues...budget, security etc see this link
http://ujenzibora.com/nahinga/?p=433"..I am because we are. "― Ubuntu, Umtu,