Warlike Tiger, Good Morning. Whats your dilemma. Is it the budget, design plan or availability of a professional to do it? Either of that would require a site study, without that it is not possible to estimate the plans or costs or even a realistic design plan. If you are keen , you can search for professionals in this forum and contact them or leave your number for interested architects to call you. However, this idea of building the second story and then breaking the lower floor walls is not feasible. It is a hilly area and you should be all the more cautious with the foundation. Hope this helps! Amit CORNERSTONE DESIGNS Bangalore.

Dear Mr. Shekhar , Although your requirements are not complete but still considering your mentioned things i think your plot is not very big. Its hardly 1000sqft plot. Also depending onto the local by-laws, you would never be able to use 100% of your land as buildup. Your design process needs special attentions. Check out my profile and projects and let me know if I can help. - Ar. Ravi Prakash

Hi Sahil, Just mentioning the plot size is not good enough and appreciable to get inputs from professionals. Designing is a subjective process thats why every house is different from another. you better provide with the other information like layout, orientation, your requirements etc. only then any professional here would be able to help you.

As it's a North facing house, I would suggest keeping most of the openings to the north, will illuminate your house beautifully and will lessen your electricity bill. A duplex will be suitable according to the area and requirement. That will allow keeping a lot of open space which will give the feeling of being in even larger space than it really is. I hope it helps. I could have suggested more if I knew more about the project.