A one-section home removes marriage-line assembly, but it does not remove route, site, foundation, anchoring, utility, exterior, inspection, correction, or closeout work.
Short answer: A single-wide setup quote should identify the exact home and installation instructions; delivery distance and route; permits, escorts, access, staging, and placement; support or foundation system; anchoring and leveling; utility and trade connections; weather closure and trim; steps, landings, decks, skirting, gutters, drainage, and cleanup; permits, inspections, corrections, warranty, and final records. The cost changes with the written scope and site—not simply because the home is one section.