BoatCostReal ownership math

Boat maintenance schedule and annual budget

How to think about recurring boat service — engines, bottom, safety gear — and how BoatCost’s maintenance percent relates to a real shop calendar.

Maintenance is the line owners either forget or mythologize. BoatCost uses a percent of purchase price so every page has a number. Real shops bill hours, parts, and surprise corrosion. This guide maps a practical calendar onto that percent so you know when to override it.

The ownership calculator maintenance override wins, including 0. Zero is a good way to see the rest of the stack. It is a bad way to own a 200-hour outboard.

The planning percents

A $45,000 pontoon is $1,350 a year in the model. A $120,000 center console is $6,000. A $16,000 PWC is $960. Those are not invoices. They exist so a console is not treated like a pontoon.

If last year you spent $2,200 on oil, an impeller, and a battery, enter 2200. If this year you need a lower unit, enter a larger number. A smooth percent cannot see a gearcase.

A calendar that is not a survey

The following is ordinary manufacturer-shaped practice, not a statistical study and not a substitute for the owner’s manual.

Every outing

Every 50–100 hours or annually (whichever the manual says)

Seasonally, climate depending

Multi-year / lumpy

The calculator has one maintenance number. Fold lumpy years in when you know they are coming. Do not average a new powerhead over ten years in your head and then forget to save.

Type notes

Pontoons. Furniture, vinyl, and logs. The 3% figure assumes you are not refinishing a tritoon every spring. Fence gates and toon leaks are still real.

Bowriders. Sterndrives are a shop type. Outboards trade bellows for different corrosion. The 4% default does not know which you have.

Center consoles and bay boats. Salt, T-tops, and electronics eat money. The 5% console factor is the model’s way of saying that. Hours on the fuel calculator should match the hours you will also service.

PWC. Jet pumps eat debris. The 6% factor is a warning, not a Yamaha schedule.

Cabin cruisers. Heads, air-conditioning, generators, and twins. 4% of a large price is a lot of dollars and still might be light in a yard-heavy year.

Sailboats. 3% of price plus a wet slip can still be the expensive boat. Rigging is lumpy. Use the override.

What maintenance is not

If you finance a refit, add it to price or keep it out of the tool and remember it exists.

Hours are the hidden multiplier

A boat with 20 hours and a boat with 200 hours do not share a shop year. The model does not scale maintenance with hours — only fuel does. That is a limitation. If you are a high-hour fishing owner, raise the override. If the boat sits, do not assume 4% goes to zero; sitting creates its own decay (seals, mice, varnish in fuel).

Cost per outing still uses the full annual maintenance. Sitting is not a discount.

Records worth keeping

A folder with invoices, impeller dates, and gearcase photos is worth more than a forum thread. Buyers of your future boat will pay for evidence. Insurers sometimes ask after a claim. The calculator will not store the folder — this site has no accounts — but your share link can include a maintenance override that matches the folder’s latest year.

If you are shopping used and the seller has no records, do not use a 3–4% default as comfort. Use a survey and a compression or running test, then enter a fatter override for year one.

How to build a number you trust

  1. List last year’s invoices if you own the boat.
  2. If you are buying, ask for service records and a survey.
  3. Add a round number for the next lumpy job.
  4. Enter the sum as the override.
  5. Re-run buy vs rent if the shop pile plus slip loses to a club.

State pages such as cabin cruiser in New York and pontoon in Arkansas change storage and insurance more than they change the maintenance percent. The percent is type-based.

Pros and cons of a percent of price

Pros

Cons

Corrosion, paint, and the environment you actually use

Freshwater lake boats and saltwater slip boats do not share a zinc budget. The maintenance percent does not know which water you chose. If the state page is coastal — bay boat in Maryland, center console in Louisiana — assume more anodes, more washes, and more electrical gremlins than a reservoir pontoon. Put that in the override instead of hoping 5% is magic.

Bottom paint is a wet-slip tax. Trailer boats skip it and pay ramp time. That trade is the point of wet slip vs trailer. Do not count bottom paint in maintenance and also forget it when you switch to trailer in the tool.

Who this is for

If you share a boat with a partner, write down who books the impeller and who pays. Shared ownership fails when both people thought the other scheduled the gearcase. Put a calendar reminder on the hour interval the manual states, not on “sometime in April.”

Alternatives

Related

FAQ

Should I enter oil changes only? Enter the annual total you believe, not the pleasant part.

Does diesel lower maintenance in the model? No. Diesel changes fuel SFC. Maintenance stays on type percent unless you override.

Why override to 0 for a thought experiment? To see fixed costs alone. Put a real number back before you compare boats.

Questions

What maintenance percent does the calculator use?
Pontoon and sail 3% of price, center console 5%, PWC 6%, everything else 4%, unless you override.
Is that a survey of shop invoices?
No. It is a smooth planning percent. Lumpy jobs (engines, sails, bottom) belong in the override when you know them.
Does paid-off change maintenance?
No. The engine does not care that the note is gone.

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