You have a great opportunity to go eclectic. So using very modern and colourful elements for the kitchen - modern storage cannisters, a vase, lights, toaster, even mixer, you start to introduce shocks of colour and shape that jar with the expectations in a traditional kitchen. In this image see how the chairs just add a touch of cheek to cheer up the kitchen...

Please consider this reorganization of the spaces which makes the most off the area available. The dining area is moved from the dark interior to share the same area as the living room, across from the open kitchen counter which would serve as a buffet. The black volumes are false columns faced in stone or marble or any other material of your choosing to give the space some girth. This distribution of the spaces gains you a walking closet for the master bedroom. Its ultimate effectiveness depends on your needs. I hope this is somewhat useful.

For the living room, the focus should be the balcony area. So flipping the couch to face the wall and not the dining table will help. Kind of like this pic. Even if you already have the sectional that is in the diagram, you should be able to flip it. In fact a sectional would probably work better than the couch in this pic. I also really don't like the style of this pic, but it showed what I meant, For the girls' room: No matter which bedroom you choose, you should maximize floor space so that they have the biggest play space possible in their room (as they get older you can add desks for school work and such). To get this space, I would give them bunk beds. This configuration gives them an open feel and more storage, essential for girls. You posted two different kitchen designs. This makes it hard to give you advice. I agree with other posts that your sink should be away from the wall. This allows you to have stuff to the left of you (drying dishes in my house), while you wash vegetables on the right of the sink. You need the same space on both sides of the stove, also. At least 24 inches on both sides is good. 36 is better, though. The first design has a nice little countertop space that adds a place for your daughters a space to sit a watch/ talk to you while you're in the kitchen. When they added this to the first design, you lost cabinets on the other wall. This is bad, as the space is already storage limited. Try making the rounded countertop bump out into the living space more. If you play with the shape, you could make it work without losing the cabinets on the other side. It doesn't have to be rectangular or a perfect circle. You can see how this one isn't confined to the floor plan of the kitchen. I think this is what you would need to do to make it the most functional.

Dear Ms. Saranya, Since you are planning to design an entire flat of 2 BHK, you would need to collect quotations from different design firms and vendors as well. Usually, an interior project cost is determined by the client's budgetary constraints and decor requirements. It is very complex to put a per sqft cost on a house design because it depends on the prices of decor and materials along with the level of workmanship. However, on a general scale, it costs anything between 800-2000 /sft depending on the furniture and furnishings you want to use. Regards, Aurum Ideas and Spaces Bhubaneswar.