The Bluebirds are currently preparing to begin their first campaign back in the Premier League, and Warnock has made a total of six additions to his first-team squad.
However, the manager has said that one of his top targets for the summer had been Lerma - who has now joined Bournemouth - but the club immediately put off by Levante's asking price.
Warnock told talkSPORT: "Our number one target in midfield was the lad Bournemouth signed, Lerma. We thought it'd be about five or six million, and I think they paid about £27m.
"We had a rude awakening early doors. We were quite a long way away from the top targets so we had to be realistic really."
Lerma could start for Bournemouth against Cardiff on Saturday afternoon.