Thank you all for your reply ,much appreciated. Since the size is rectangular I feel more of modern look. I would love to have a Victorian or a classy look though. Also I am allowed to construct roughly around 1800 to 1900 sqft. The plot entry is from the width(10sqmtr) side, so some more restriction. I am from Mumbai (India ) , the climate here is kind of extreme.Though the coolest can go max to 10 degree Celsius and the hottest can go max 45 degree Celsius. This will be my dream place where I would like to call in friends and family, though there is no pool , I would like to have a plunge pool kind of at the rooftop.A small sitting lounge to entertain guest. Sine it a small size , I am limited to doing all this stuff mostly at the roof top. Please advice.Thank you

Consider composite decking material which are more durable.

I did a house with nine bathrooms and it was so much fun. For the master bed we had his and hers separate ensuite bathrooms, so hers was feminine and victoruan; it even had a chandelier! His was white with a red shower wall and a blue and white border tile. The counter was tiled with red. It was a very cheerful little bathroom. The daughter's batH was blue and white, the border tiles and washbasin were Chinese themed. A very pretty bathroom. The two guest bathrooms were yellow and cream with hand painted sunflower accent tiles. One powder room was yellow and white, the other was beige with orange and green accents. It had a very whimsical washbasin with a hand painted frog inside. The pool house also has two bathrooms, more basic, mostly cream with wood accents. The colour comes from the stack of towels, red, blue, orange, lime green and yellow.

Around 5 lakhs for average size 10'x20', 6' depth inground. Obviously it can only go higher if you need jets, underwater lighting etc Maintaining a pool takes away all the fun of enjoying it. Unless of course if you have maintenance staff. The terrace first needs to be designed to support the weight of the pool. If it is, and a sunken area has been created for the pool, then it would still work out close to the inground pool cost as we will need to ferry materials up. If budget is a constraint you can go for a white cement render Plunge pool instead like one below. It is also far easier to maintain than a full scale swimming pool.