The overall cost depends on the area you would like to build (GF+FF). The cost I am hearing is about 1500-1800/sq ft depending on the area finish etc. Further such sloped roofing could steeply increase on the overall budget.
No doubt the arch design is good, however I am not sure how practical it would be for India as such houses are made for European kind which doesn't have boundary walls etc and adds to the beauty which is enhanced by the surroundings. However in India a house without boundary wall is not practical, unless it is in a gated community kind. So think about it.