Hidden construction costs: connections, drainage, and design

"Building a house for £100,000" — and then it ends up being £120,000. Not because prices rose, but because no one mentioned the line items that are not included in the "house" price estimate. ## Most commonly overlooked items - Connections — electricity (£1,000–£4,000), water (£1,000–£3,000), gas (£1,000–£3,000) depending on the distance from the network. - Technical conditions and approvals — maps, land development projects: £400–£1,600. - Site manager — mandatory for many investments: £160–£500/month. - Surveying and layout — £200–£600. - Acceptance tests and measurement protocols — electricity, ventilation, chimneys: £300–£800. - Construction insurance — 0.2–0.5% of the total works value. - Land development — driveway, external stairs, fencing: £2,000–£10,000. ## What it adds up to In reality, 10–15% of the construction budget consists of costs that you do not see in the "price per m²" of a house. ## How not to miss them 1. Ask for a cost estimate including a section for "supporting works and formalities." 2. Ask directly: "what else do I need to buy or arrange outside of this quote?" — and write down the answer. 3. Inquire about connection conditions at the land purchase stage — this is the only moment to negotiate with utility providers. When posting a job on LocalTrader, describe the plot and the distances to utilities — companies will include connections in their offers immediately.