What is the time for the wedding feast (waleemah)?
Question

                I am going to get married, in sha Allah, and I want to follow the Sunnah of the Messenger (blessings and peace of Allah be upon him) by offering a wedding feast (waleemah). My question is: when is the right time to do it? What is the number of people to be invited? Please note that in our country the invitation and offering food is done before the marriage contract is done. Is this regarded as a waleemah and will this duty then be waived if one does that?.
Praise be to Allah.
    Firstly: 

    It is best to do the wedding feast (waleemah) after the 
    marriage is consummated, following the example of the Prophet (blessings and 
    peace of Allah be upon him). But if that is not possible, then there is 
    nothing wrong with doing it before the marriage is consummated, or when the 
    marriage contract is done, or after that. 

    The matter is broad in scope, but it is better to pay 
    attention to what is usually done in your country, because there is no 
    shar‘i text to indicate that it is obligatory or mustahabb to do it at a 
    certain time. 

    Al-Haafiz Ibn Hajar said: The salaf differed concerning the 
    time (for the wedding feast): should it be at the time of the marriage 
    contract, or after it, or just before consummation of the marriage, or after 
    that; it could be at any time from when the marriage contract is first done 
    until after the marriage is consummated. There are several scholarly 
    opinions. End quote. 

    Fath al-Baari, 9/230 

    As-San‘aani said: 

    Al-Mawardi, one of the Shaafa‘is, stated that it should be 
    just before consummation of the marriage. 

    As-Sibki said: What has been narrated concerning the action 
    of the Prophet (blessings and peace of Allah be upon him) is that it comes 
    after consummation of the marriage. 

    It is as if he was referring to the story of the marriage of 
    Zaynab bint Jahsh, because Anas said: When the day dawned, the Prophet 
    (blessings and peace of Allah be upon him) was a bridegroom to Zaynab, and 
    he invited the people (to a meal). 

    Al-Bayhaqi included this hadeeth under the heading: Chapter: 
    The time of the waleemah. 

    End quote from Subul as-Salaam, 1/154 

    The hadeeth of Anas was narrated by al-Bukhaari (4793) and 
    Muslim (1428) as follows: When the day dawned the Messenger of Allah 
    (blessings and peace of Allah be upon him) was a bridegroom to Zaynab bint 
    Jahsh, whom he married in Madinah, and he invited the people to eat in the 
    forenoon. 

    According to a version narrated by al-Bukhaari (5166): When 
    the day dawned, the Prophet (blessings and peace of Allah be upon him) was a 
    bridegroom to her, then he invited the people and they had some food. 

    Shaykh al-Islam Ibn Taymiyah said: The time and description 
    of the waleemah in the hadeeth of Zaynab indicate that it followed 
    consummation of the marriage. End quote. 

    Al-Ikhtiyaaraat al-‘Ilmiyyah, p. 
    346 

    Al-Haafiz Ibn Hajar said: The hadeeth of Anas clearly 
    indicates that it came after consummation, because he said: “When the day 
    dawned, he was a bridegroom to Zaynab and he invited the people …” 

    Some of the Maalikis regarded it as mustahabb for it to just 
    before consummation, which should come after it, and this is what people do 
    nowadays. End quote. 

    Fath al-Baari, 9/231 

    Al-Mardawi said: It is better to say that the recommended 
    time is flexible; it may be at any time from when the marriage contract is 
    done until the end of the days of the wedding. 

    That is because there is a report to support that, and 
    because joy is greatest after consummation. But the custom nowadays to do it 
    shortly before consummation. End quote. 

    Al-Insaaf, 8/317 

    Al-Bukhaari said: Chapter on the duty to accept invitations 
    to wedding feasts; the one who gives a waleemah for seven days and the like; 
    the Prophet (blessings and peace of Allah be upon him) did not specify that 
    it should be for one or two days. 

    Al-Haafiz said: i.e., he did not set a specific time for the 
    waleemah or say that it is obligatory or mustahabb; that may be understood 
    from the general meaning of the hadeeth. 

    Ad-Dameeri said: The fuqaha’ did not set a specific time for 
    the wedding feast, but the correct view is that it should be after 
    consummation of the marriage. The shaykh (i.e., as-Sibki) said: It is 
    permissible to do it before or after; the matter is flexible and it may be 
    done at any time after the marriage contract is done, as was stated by al-Baghawi 

    Al-Najm al-Wahhaaj, 7/393 

    Ibn Tuloon said: The more correct view is that one should 
    refer to what is customary.

    End quote from Fass al-Khawaatim fima qeela fi’l-Walaa’im, 
    p. 44 

    Shaykh Saalih al-Fawzaan said: The time for giving the 
    wedding feast flexible, starting from the time of the marriage contract 
    until the end of the days of the wedding.

    End quote from al-Mulakhkhas al-Fiqhi, 2/364 

    Secondly: 

    There is no set number of guests to be invited; rather that 
    depends on what a person can afford. 

    Ibn Battaal said: The waleemah (wedding feast) is obligatory, 
    according to one’s means. There is no minimum number of people that must be 
    invited.

    End quote from Sharh Saheeh al-Bukhaari, 13/283 

    And he said:

    The more you add (to the number of guests) at the wedding 
    feast the better, because that helps to announce the marriage more widely 
    and increases the supplications for blessing of one’s family and wealth.

    End quote from Sharh Saheeh al-Bukhaari, 13/282. 

    And Allah knows best.