Buyers typically pay for fiber laying by combining material costs, labor time, and permitting plus trenching or aerial support fees. The main cost drivers are trench depth, fiber count and type (single-mode vs multi-mode), conduit requirements, and local permitting rules. Total Project Costs: For commercial installations, expect costs ranging from $5,000 to $20,000 per mile for underground projects and from $40,000 to $60,000 per. Home and business fiber optics projects typically range from a few hundred to several thousand dollars, depending on run length, fiber type, and labor needs.