Al-Walima is to be given even with one sheep

Narrated Anas:

When 'Abdur-Rahman bin 'Auf married an Ansari woman, the Prophet asked him, "How much Mahr did you give her?" 'Abdur-Rahman said, "Gold equal to the weight of a date stone." Anas added: When they (i.e. the Prophet and his companions) arrived at Medina, the emigrants stayed at the Ansar's houses. 'Abdur-Rahman bin 'Auf stayed at Sad bin Ar-Rabi's house. Sad said to 'Abdur-Rahman, "I will divide and share my property with you and will give one of my two wives to you." 'Abdur-Rahman said, "May Allah bless you, your wives and property (I am not in need of that;
but kindly show me the way to the market)." So 'Abdur-Rahman went to the market and traded there gaining a profit of some dried yoghurt and butter, and married (an Ansari woman). The Prophet ﷺ said to him, "Give a banquet, even if with one sheep."

حَدَّثَنَا عَلِيٌّ، حَدَّثَنَا سُفْيَانُ، قَالَ حَدَّثَنِي حُمَيْدٌ، أَنَّهُ سَمِعَ أَنَسًا ـ رضى الله عنه ـ قَالَ سَأَلَ النَّبِيُّ ﷺ عَبْدَ الرَّحْمَنِ بْنَ عَوْفٍ وَتَزَوَّجَ امْرَأَةً مِنَ الأَنْصَارِ " كَمْ أَصْدَقْتَهَا ". قَالَ وَزْنَ نَوَاةٍ مِنْ ذَهَبٍ. وَعَنْ حُمَيْدٍ سَمِعْتُ أَنَسًا قَالَ لَمَّا قَدِمُوا الْمَدِينَةَ نَزَلَ الْمُهَاجِرُونَ عَلَى الأَنْصَارِ فَنَزَلَ عَبْدُ الرَّحْمَنِ بْنُ عَوْفٍ عَلَى سَعْدِ بْنِ الرَّبِيعِ فَقَالَ أُقَاسِمُكَ مَالِي وَأَنْزِلُ لَكَ عَنْ إِحْدَى امْرَأَتَىَّ. قَالَ بَارَكَ اللَّهُ لَكَ فِي أَهْلِكَ وَمَالِكَ. فَخَرَجَ إِلَى السُّوقِ فَبَاعَ وَاشْتَرَى فَأَصَابَ شَيْئًا مِنْ أَقِطٍ وَسَمْنٍ فَتَزَوَّجَ فَقَالَ النَّبِيُّ ﷺ " أَوْلِمْ وَلَوْ بِشَاةٍ ".

Narrated Anas:

The Prophet did not give a better wedding banquet on the occasion of marrying any of his wives than the one he gave on marrying Zainab, and that banquet was with (consisted of) one sheep.

حَدَّثَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا حَمَّادٌ، عَنْ ثَابِتٍ، عَنْ أَنَسٍ، قَالَ مَا أَوْلَمَ النَّبِيُّ ﷺ عَلَى شَىْءٍ مِنْ نِسَائِهِ، مَا أَوْلَمَ عَلَى زَيْنَبَ أَوْلَمَ بِشَاةٍ.

Narrated Anas:

Allah's Apostle manumitted Safiyya and then married her, and her Mahr was her manumission, and he gave a wedding banquet with Hais (a sort of sweet dish made from butter, cheese and dates).

حَدَّثَنَا مُسَدَّدٌ، عَنْ عَبْدِ الْوَارِثِ، عَنْ شُعَيْبٍ، عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ ﷺ أَعْتَقَ صَفِيَّةَ، وَتَزَوَّجَهَا وَجَعَلَ عِتْقَهَا صَدَاقَهَا، وَأَوْلَمَ عَلَيْهَا بِحَيْسٍ.