How to Fish boat upgrades: motors and radar costs

The boat starts with Small Motor. Medium Motor costs $230 and first appears on Island 2; Big Motor costs $860 and first appears on Island 4. Navigation has two separate purchases: the $10 handheld Radar and the $200 boat-mounted radar upgrade.

Motor prices and availability

The source force values describe the motor setup, not measured travel speeds. A change from force 800 to 2,000 does not establish that every journey takes 40% as long. Boat handling and the route still matter.

Use the linked motor records or the map for sellers. Prices are the active purchase values for 1.0.12. The world's money balance is shared in co-op.

Do you need to buy Medium Motor first?

The motor purchase checks that the requested tier is higher than the boat's current tier. It does not require buying every intermediate tier. If you reach a Big Motor seller with the starting motor and enough money, the higher tier is eligible.

Buying Medium Motor earlier is a choice about the time you spend traveling before Island 4. There is no measured route saving here that makes it mandatory. Once a higher motor is installed, an equal or lower tier is not an upgrade purchase.

Those achievements do not require every attachment, a radio or both radars. The all-achievement checklist separates boat upgrades from the weapon achievement Fully equipped.

Handheld Radar versus boat radar

Handheld Radar shops continue on Islands 2 through 5. Boat radar sellers are on Islands 3, 4 and 5. The mounted upgrade is recorded on the boat; it is not another handheld item to find in your inventory.

Buying either radar does not replace a quest's coordinate reward. After each passage request, take the offered keys or flash drive. If the next island is unavailable, check the required hand-in sequence before buying another navigation item.

The boat is still locked

On Island 1, return the Spider Crab Shell to the Lighthouse Keeper and take the offered boat keys. The boat walkthrough covers that exchange. Purchasing Radar is separate and does not claim the keys for you.

Later upgrades improve the boat you already have. They do not skip the Piranha, Pufferfish, Albatross or final whale hand-ins. For a Bean route, budget motor purchases against weapons and required bait rather than treating every upgrade as compulsory.

Is the flying-boat achievement a motor upgrade?

No. I'm the bird now checks the boat's height, not its motor tier. A fast motor alone does not satisfy that check. The trick-achievement guide explains the height condition and why there is no verified one-size-fits-all explosive setup.