She has enough money to do Hajj but she does not have a mahram
Question

                I am a single woman from Morocco, and I am 35 years old. I have quite a lot of money (and I do not think I will ever have this much again). After thinking for a long time, I decided that I could not find anything better to spend it on than going to the sacred House of Allaah, to perform the obligatory duty of Hajj, as I long to visit that place. This is my hope in life, and I hope that Allaah will not deprive me of that hope. The problem is that I do not have any mahram. My brother cannot go because he is not well off, and the same applies to my father. I hope that you can advise me and find a solution to this problem for me.
Praise be to Allah.It is not 
    permissible for a woman to travel without a mahram, even if she is 
    travelling for the obligatory Hajj or obligatory ‘Umrah, according to the 
    more  correct of the two scholarly opinions, because of the report narrated 
    by al-Bukhaari (1729) and Muslim (2391) from Ibn ‘Abbaas (may Allaah be 
    pleased with him) who said: The Prophet  (peace and blessings of Allaah 
    be upon him) said: “No woman should travel except with a mahram, and no man 
    should enter upon her unless there is a mahram with her.” A man said: O 
    Messenger of Allaah, I want to go out on such and such a campaign, and my 
    wife wants to go for Hajj.” He said: “Do Hajj with her.” 
Because of 
    this hadeeth and others which indicate that it is haraam for a woman to 
    travel without a mahram, a number of scholars are of the view that the 
    presence of a mahram is one of the conditions of Hajj being obligatory for a 
    woman. So if you cannot find a mahram to travel with you, Hajj is not 
    obligatory for you, and you are excused, but will be rewarded for your 
    intention in sha Allaah. 
Imam Ahmad 
    (may Allaah have mercy on him) was asked about a woman who was well off but 
    did not have a mahram – is Hajj obligatory for her? He said: No. 
Al-Mughni 
    (3/97). 
The Standing 
    Committee was also asked (11/95): I have a problem for which I want to find 
    a solution from Allaah, who is Merciful towards His slaves. It has to do 
    with my performing the obligation of Hajj. I am a woman in my fifties and 
    for two years I have wanted to travel to perform the obligatory Hajj. What 
    is preventing me from travelling is that I do not have a mahram who can 
    travel with me. My husband has no concerns except work and worldly matters, 
    and he does not intend to travel for Hajj, unless it is arranged for free by 
    the company for which he works. That will not happen until his turn comes, 
    and I am afraid that I may die before I perform this duty. I have enough 
    money to pay for provisions and the journey. To sum up: all my mahrams are 
    unable to travel with me because of their work.  
They 
    replied: 
If the 
    situation is as described, and neither your husband nor any of your mahrams 
    is able to travel with you so that you can perform the obligatory Hajj, then 
    you are not obliged to do it so long as this situation persists, because the 
    presence of your husband or mahram for the journey to Hajj is one of the 
    conditions of it being obligatory for you. It is haraam for you to travel 
    for Hajj or any other purpose without a mahram, even with your brother’s 
    wife and a group of women, according to the more correct of the two 
    scholarly views, because the Prophet  (peace and blessings of Allaah be 
    upon him) said: “No woman should travel except with a mahram.” Saheeh – 
    agreed upon. Strive to do righteous deeds which do not require you to 
    travel, and be patient, in the hope that Allaah will make things easy for 
    you and grant you the means of travelling with your husband or a mahram. End 
    quote. 
Fataawa 
    al-Lajnah al-Daa’imah (11/95) 
We ask Allaah to guide us and you. 
And Allaah knows best.