you can immediately (even at beginning of game) chase enemy tiny Sloops with your huge HMS Victory if you want :-) Premium ships can be bought for real money at any time, so e.g. Be warned that more unlocked maps means increased difficulty of enemies! The best ships will be spawned if you discover Panama Coast (discovering remaining regions doesn’t affect the ship spawning). If you own more maps there is more probability that better ship will be spawned.
Ships (which you can encounter in the open world), blueprints and treasure maps depends on how many maps you own.
