What happens to the estimate if I add a swimming pool later?

A swimming pool is not included in the base villa estimate and needs its own specialist costing, since pool structure, filtration, waterproofing and deck finishing follow a very different cost logic than habitable built-up area. If a pool is part of your eventual plan, mention it at the design stage so structural provisions, such as adjacent slab loading and drainage, are considered even if construction is phased. Adding a pool as a pure afterthought after the main structure is complete is far more disruptive than planning for it upfront.