What are the consequences if a prospective husband lies about his status, job or income during the engagement?

Deception during khitbah is a sin and gives the deceived party the right to break off the engagement; if already married, it may be the basis of a claim in court.
Deception about basic matters such as marital status, religion, occupation or large debts undermines consent, whereas marriage is built on honest agreement. Before the contract, the deceived party may withdraw without being counted as breaking a promise, and may claim the return of gifts and expenses. After the contract, the effect depends on the type of deception and the Syariah court's decision, for example fasakh or action relating to polygyny without permission. Protect yourself: check documents, get to know his family, and involve the wali. See khitbah.