Winterization Cost Calculator

This calculator builds up a winterization estimate system by system, the way a marine service department typically itemizes the job. Engine service is the anchor cost and scales with both engine type and count: outboards are cheapest to winterize ($120/engine — fog cylinders, stabilize fuel, flush, lower-unit lube), while inboard diesels are the most expensive ($450/engine) because they need a full cooling flush, oil and filter change, antifreeze, and fuel treatment; multiple engines multiply that cost linearly. Fresh water and head/plumbing systems scale per foot of boat length, reflecting that a longer hull generally means more tankage and more line to purge and antifreeze.

Optional systems — generator, air conditioning — add flat service fees only when selected, and battery service scales with engine count (one battery bank tends to accompany each engine). A 15% materials markup is applied to the labor subtotal to cover antifreeze, oil, filters, and fuel stabilizer, and shrink wrap (about $14/ft when selected) plus a flat $5/ft storage-prep charge are added on top, since those are priced independently of the mechanical work. The biggest source of real-world variance this model doesn't capture is regional labor rates and boat-specific complications like non-standard raw-water strainers, multiple heads, or built-in ice makers — treat this as a solid ballpark for planning a fall haul-out budget, not a substitute for an itemized yard quote.