The most expensive mistake: the drain plug
Asked what the most expensive mistake a boat owner makes is, Mike's answer was not an engine fault. It was forgetting the drain plug. Launch without it and the boat starts filling the second it floats. Once that water reaches the engine, the wiring and the fuel system, your spring launch has turned into a salvage-and-repair job.
It is the simplest item on any launch checklist, and the one that costs the most when it is missed.
A lesson from a pontoon: check for factory coatings
One job that went wrong taught its own rule. A pontoon came out for a bottom wash, and it had a Sharkhide protective coating on it. Bottom washes are routine at haul-out. A factory or aftermarket protective coating, though, changes what's safe to do to the metal underneath.
The lesson Mike took from it: double-check for factory protective coatings before any bottom wash. Know your pontoon or hull's been coated? Say so on the call. If you don't know, it gets checked.
Spring launch, paired with commissioning
Ice-out on Lake Winnipesaukee is declared in April in most years, and spring is one of the two booked-out seasons. A boat commissioned before launch — batteries in and charged, impeller and belts checked, fuel system and engine run up — goes in the water ready to use, rather than getting to the dock and finding out what the winter did.
Fuel is worth a word here, too. The other owner mistake Mike names is poor-quality fuel, and a boat that sat all winter on old fuel is one way to make it. It shows up as a hard start or a rough idle on launch day, which is the worst possible day to find it.
Fall haul-out, paired with winterization
Out of the water is when you see what the season did. Bottom, drive or lower unit, prop and anodes, all visible for the first time since spring. Winterization comes next: fogging, fuel stabilized, water drained out of everything that holds it, gear lube changed, batteries dealt with, and the boat covered or wrapped.
Fall is the other booked-out season, so an early booking is the one that gets a choice of date.