The evidence for this is that taking payment for permissible work is absolutely correct because this is earning wages for labor on Allah’s bounty (trade), and taking this wage is permissible.

Abu Umamah al-Taimi narrates that I said to Sayyiduna Ibn Umar (may Allah be pleased with them), "Indeed, during the journey of Hajj, we provide riding animals to people on rent, and my people say that our Hajj is not valid (because we drive the camels that are given on rent)." Sayyiduna Ibn Umar (may Allah be pleased with them) said, "Do you not perform the Tawaf of the House of Allah? Do you not perform the Sa'i between Safa and Marwah? Do you not perform such and such acts of Hajj?" Indeed, a man came to the Prophet (peace and blessings be upon him) and asked him the same question as you have asked me. The Prophet (peace and blessings be upon him) did not know the answer until this verse was revealed «‏‏‏‏لَيْسَ عَلَيْكُمْ جُنَاحٌ أَن تَبْتَغُوا فَضْلًا مِّن رَّبِّكُمْ» ‏‏‏‏ [ سورة البقرة: 198] "There is no sin upon you that you seek the bounty of your Lord (during Hajj)." So the Prophet (peace and blessings be upon him) called that man, recited this verse to him, and said: "You are also a pilgrim (Haji)."

The Imam narrated another chain of transmission for the previous hadith.

And the evidence that if the hired person rents himself out for such-and-such, and performs Hajj on behalf of himself, then the wage belongs to him from his employer, and the performance of the obligation on behalf of himself is permissible.

Saeed bin Jubair (may Allah have mercy on him) narrates that a man came to Sayyiduna Ibn Umar (may Allah be pleased with them both) and said, "I offered myself for work to a people, then I left my wages or all of my wages on the condition that they would allow me to perform the rites of Hajj. So will my Hajj be sufficient for me?" Sayyiduna Ibn Umar (may Allah be pleased with them both) replied, "Yes, this person is among those about whom Allah Almighty has said «‏‏‏‏أُولَٰئِكَ لَهُمْ نَصِيبٌ مِّمَّا كَسَبُوا ۚ وَاللَّهُ سَرِيعُ الْحِسَابِ» ‏‏‏‏ [ سورة البقرة: 202] 'For such there is a share of what they have earned, and Allah is swift in taking account.'"

And the evidence that engaging in what Allah has permitted of seeking wealth from its lawful means during the days of the season, outside of the times in which a person is occupied from performing the rites, does not diminish the reward of the pilgrim, nor does it invalidate the Hajj, nor does it obligate upon him a sacrifice, nor fasting, nor charity.

It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that previously, when people used to buy and sell in Mina, Arafah, and the market of Dhul-Majaz during the season of Hajj, then they became afraid that they were buying and selling while in the state of Ihram. So Allah Almighty revealed this verse «‏‏‏‏لَيْسَ عَلَيْكُمْ جُنَاحٌ أَن تَبْتَغُوا فَضْلًا مِّن رَّبِّكُمْ» ‏‏‏‏ [ سورة البقرة: 198] "There is no sin upon you that you seek the bounty of your Lord (during Hajj)." Ubaid bin Umair narrates that Sayyiduna Ibn Abbas (may Allah be pleased with them both) used to recite these words in the Qur'an along with the verse during the seasons of Hajj.

Ubaidullah bin Abi Yazid narrates that I heard Sayyiduna Ibn Zubair (may Allah be pleased with him) reciting this verse in this way «‏‏‏‏لَيْسَ عَلَيْكُمْ جُنَاحٌ أَن تَبْتَغُوا فَضْلًا مِّن رَّبِّكُمْ فِى مَوَاسِم الْحَجّ» ‏‏‏‏ "There is no sin upon you that you seek the bounty of your Lord during the season of Hajj."

And the evidence against what the common people have imagined is that the Prophet, peace and blessings be upon him, did not perform Hajj except one Hajj, and the Prophet, peace and blessings be upon him, only performed one Hajj after his migration to al-Madinah. As for before the migration, the Prophet, peace and blessings be upon him, performed Hajj other than that Hajj which he performed from al-Madinah.

It is narrated from Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) performed three Hajj: two before the migration and one Hajj after the migration, and with it was also an Umrah. In the narration of Ahmad bin Yahya, it is mentioned: and one was that Hajj in which you combined Umrah with it (and it was performed after the migration to Madinah).