Your house in Parklands? The layout look familiar.    I guess 2.0HP will be well enough for the living hall. Unless u wanted to blow the living hall & dining hall together then you may required 2.5HP.

Yup. I'm from Parklands too. I guess urs is Tulip but mine is Freesia. Initial stage I wanted to buy Tulip also because of its better looking car porch floor, biggest store room & nice looking switches. 

Is it? Mine is half way renovated. Still need another 2 months. MPK renovation permit is very easy to settle. Need some infos? But I guess ur contractors will guide you all the way. BTW, who is ur contractor?

It also depend whether any glass door to block the aircon go behind (kitchen area), else never been cool and your a/c will keep running non stop.