The other thing to consider is the quality of the space. The rooms created would be just under 3m x 3m (approx 9ft x 9ft) which would be very tight for a double bedroom. So this means this space could be used for a small bedroom or perhaps bathroom or dressing room depending on how the internal layout turns out.
One mistake homebuyers often make when looking at floor plans is over spending for the future, rather than planning for the present. You can always upgrade your home. From finishes and innovative additions to possibly adding area and amenities. Don't get oversold from a home selling agent or a developer's representative – only you know your budget. Plan for your budget now so you will feel comfortable living in your home and not feel “financially strained” each month to make payments on your home.