The shell you already own
The most underused building in any district is the one the client already lives in. Renovation has a bad reputation because it is usually attempted backwards: rooms are redecorated before the building is understood, and the money runs out before the plan is fixed.
The practice's record holds a clean counter-example. In 2005, the project recorded as RCS Flour Mill, Ashish Singhal Residence on GT Road was an interior and renovation job inside an existing two-floor, five-thousand-square-foot building. What makes it worth writing about is the level of detail the family worked at: a drawing room of fifteen by eighteen feet, a family lounge of twenty-four by fifty, a bedroom of fourteen by eighteen. Those are working dimensions, not brochure ones. The family knew how they lived, and the renovation served the living instead of the photograph.
The order that saves money
Every renovation I have seen succeed followed the same order, and every one I have seen fail skipped a step.
First, measure what is. Not from memory. On the wall. Existing buildings are never the dimensions the original drawings claim, and if your architect starts from the claimed dimensions, every following drawing is wrong.
Second, decide what deserves to stay. Structure stays. Level changes that work stay. The good twenty percent of the old work is usually the cheapest thing in the project.
Third, fix the plan before the finishes. A partition moved on paper costs a drawing revision. Moved after plaster, it costs the revision plus the plaster plus the wiring plus the week.
Fourth, spend on what you touch daily. The door handle, the bathroom floor, the kitchen counter, the light switch at the right height. These are the renovation. The twenty-four-by-fifty lounge in the 2005 record is remembered because the family used it every day, not because of how it photographed.
The things only an old building can tell you
Renovation is a conversation with the previous builders. Walls are rarely where they should be, but they are always where they are for a reason: a beam, an old pipe, a settled foundation. Find the reason before you remove the wall. The gurdwara renovation in the Delhi years, where a predecessor's wrong partition had to be un-built from a working hall, taught this the permanent way: you cannot un-build carefully what you did not build carefully.
What it costs, honestly
Renovation done in this order is the cheapest good square meterage in the district, because it concentrates the budget on change instead of on rebuilding what was fine. It is also slower in design and faster in construction, which surprises clients: weeks of measuring and deciding, then a site phase with very few surprises. The surprises were spent on paper, where they belong.
If your family is planning a renovation, the engagement starts the same way every project does, with the advance for presentation drawings, and it is staged the same way. The sequence and triggers are on how we work, the deliverables on what you receive, and more houses from the record are in the work archive.