Keelboat: Sloop/sailboat
Longboat: Coastal/riverine raiding ship
Trade Cog: Cheap, lumbering single-masted merchant ship
Lateen Caravel: Agile two-masted ship; courier/blockade runner/light trader
Round Caravel: Fast three-or-four masted ship; escort/privateer/fast trader
Trade Carrack: Large multi-masted merchantman
War Carrack: Heavy warship
Can be done primarily at Deepharbor Docks or Halefjord Docks. Prices are as follows.
Keelboat purchase price: 1,500 gold crowns
Longboat purchase price: 3,000 gold crowns
Trade Cog purchase price: 4,000 gold crowns
Lateen Caravel purchase price: 6,000 gold crowns
Round Caravel purchase price: 8,000 gold crowns
Trade Carrack purchase price: 10,000 gold crowns
War Carrack purchase price: 20,000 gold crowns
To keep it simple, each ship voyage (as long as it is under a week) can be assumed to cost 1% of the ship's purchase price - that covers operating costs, necessary maintenance, provisioning, crew wages, and harbor fees. Voyage costs are listed below.
Keelboat voyage cost: 15 gold crowns
Longboat voyage cost: 30 gold crowns
Trade Cog voyage cost: 40 gold crowns
Lateen Caravel voyage cost: 60 gold crowns
Round Caravel voyage cost: 80 gold crowns
Trade Carrack voyage cost 100 gold crowns
War Carrack voyage cost: 200 gold crowns