This sum would be more than five hundred dollars of our time.
Columbus did not give up his maritime enterprises.

He made voyages to the coast of Guinea and in other directions.
It is said that he was in command of one of the vessels of his relative Colon el Mozo, when, in the Portuguese seas, this admiral, with his squadron, engaged four Venetian galleys returning from Flanders.

A bloody battle followed.

The ship which Christopher Columbus commanded was engaged with a Venetian vessel, to which it set fire.

There was danger of an explosion, and Columbus himself, seeing this danger, flung himself into the sea, seized a floating oar, and thus gained the shore.
He was not far from Lisbon, and from this time made Lisbon his home for many years.( *) (*) The critics challenge these dates, but there seems to be good foundation for the story.
It seems clear that, from the time when he arrived in Lisbon, for more than twenty years, he was at work trying to interest people in his "great design," of western discovery.