Evening Forum, I looking for my next IP and hope to secure a 2 or 3 brm house. I am thinking that if I can't afford a 3 bdr in the area I want then I may have to look for 2 brms with enough land to possibly add another in the future. I am just weighing up some options and was wondering if anyone tell me how to calculate building an additional room or point me to previous posts, web sites etc..