Set a realistic budget with a 15 to 20 percent contingency and finalize every selection before construction starts. As of November 2025, the primary causes of budget overruns are mid-project design changes, discovering hidden conditions behind walls, and choosing materials without confirming installed pricing. A detailed scope of work with line-item pricing gives you a clear baseline, and the contingency fund covers surprises like outdated wiring or water damage that only appear once demolition is underway. Kingdom & Co. provides fixed-scope contracts with transparent line-item estimates so clients know their financial exposure before signing.