Talhah (may Allah have mercy on him) narrated from Khaythamah (may Allah have mercy on him) that a man married a woman in the time of the Prophet (peace and blessings be upon him) and consummated the marriage with her without having given anything.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصداق / 14465
Khaythamah bin Abd al-Rahman (may Allah have mercy on him) said that a man married a woman while he was in hardship, so the Prophet (peace and blessings be upon him) ordered "that he be treated gently". He consummated the marriage with the woman without giving her anything, and then, when he became well-off, he paid it.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصداق / 14466