He does not offer the prayers on time because of his work; should she accept him as a husband?
Question

                If someone who is trying to establish the 5 daily prayer but is struggling for example when they are at work and they get very busy they miss it but them make it up. but most of the time they pray at work. but they really want to change are they considered to be a kaffir and you should not marry them ect. I take the opinion that someone who abandons prayer is a kaffir but what are the opinions and evidence about the one who is trying to change and establish prayer. I have a proposal from a brother like this who my family know quite well. He is a good character but struggling regarding this but wants to marry someone who can help him be a better muslim and encourage and help him in his deen.
Praise be to Allah.
    Firstly: 

    The one who does not pray at all is a kaafir according to the 
    correct scholarly opinion. See question no.
    5208. 

    As for the one who prays sometimes and not at other times, 
    some of the scholars are of the view that he is also a kaafir. This view was 
    narrated from a number of the Sahaabah, and fatwas to this effect have been 
    issued by the Standing Committee for Issuing Fatwas, foremost among whom was 
    Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allah have mercy on him). 

    Others are of the view that he is not to be regarded as a 
    kaafir unless he does not pray at all; these scholars include Shaykh 
    al-Islam Ibn Taymiyah (may Allah have mercy on him) and Shaykh Ibn 
    ‘Uthaymeen (may Allah have mercy on him). 

    See question no. 52923 
    and 83165

    Work is not an excuse for delaying prayer until the time for 
    it has ended, because prayer only takes a few minutes. 

    If the one who wants to propose to you delays some of the 
    prayers, we do not advise you to marry him, because he is a kaafir according 
    to some of the scholars, and he is an evildoer who is committing a grave 
    major sin according to others. 

    Allah, may He be exalted, says (interpretation of the 
    meaning):

    “Then, there has 
    succeeded them a posterity who have given up As-Salat (the prayers) (i.e. 
    made their Salat (prayers) to be lost, either by not offering them or by not 
    offering them perfectly or by not offering them in their proper fixed times, 
    etc.) and have followed lusts. So they will be thrown in Hell”

    [Maryam 19:50].

    Ibn Mas‘ood (may Allah be 
    pleased with him) said concerning al-ghayy (translated above as “Hell”): It 
    is a valley in Hell, very deep and with a foul taste.

    If he announces that he has repented and has resolved to 
    offer the prayers on time, and you think that he is righteous in other 
    aspects, then there is nothing wrong with marrying him. 

    And Allah knows best.