Assalaamu alaykum wa rahmatullaahi wa barakaatuhu, Shaykh. I have a very important question regarding polygamy. I have spoken to my wife about marrying another wife; she is not happy but seems to have accepted it, so I am going to need to find out a few things regarding spending and housing before becoming serious about this. Currently, I have tried to get a property via a council, and they have delayed this property for over two months, and we have tried nearly everything to arrange for a property. So we are currently living at her parents' house. Am I still responsible to house her as I know that she will probably say that I have to get her a place to properly give her her rights even though I am in the process of getting her a place. Should I wait for a place to be confirmed and then look for a second wife, or it is ok for me to start doing that at the moment
Secondly, if we are in this stage where I am waiting for a property, am I allowed, in the mean time, to find a sister who has her own place and is happy to accept me even though I do not have my own place for my first wife (even though we are waiting for this) and is willing to accept this situation and is happy for me to marry her?
Thirdly, regarding spending; I am currently taking care of the rights of my first wife, and I will be providing her with money. How are we supposed to divide the money between wives if I am to get a second one? I do not earn that much, but I earn just enough to provide for my family. If my second wife decides that she is happy with my situation, can I marry a second wife? I would like to know; in my situation, am I going to be unjust, and is it unwise for me to marry a second wife, or should I put my trust in Allaah and carry on? Please advise me. May Allaah reward you.

All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger. 

Your wife is not obliged to live with either her relatives or yours. The Muslim wife has a right to an independent accommodation. If she claims her right and requests a separate accommodation, you are obliged to fulfill her right over you according to her status and your ability. You are not required to own the accommodation; you may rent it. The Shaafi‘i scholar Ash-Shirbeeni wrote, "It is not a condition that the house be owned by the husband; rather he may accommodate her in a house that is endowed (Waqf), rented, or borrowed." There is no difference if the man has only one wife or more than one in this regard as long as the husband provides each wife with an accommodation suitable to her own conditions.

If your financial situation is as you mentioned, then you should not seek to take a second wife. Scholars underlined that it is recommended for the man to get married if he is able to fulfill the wife's financial rights over him (dower and obligatory maintenance). The Maalikis even held that it is prohibited for the man who is financially unable to bear the responsibilities of marriage and provide for his wife to get married. The Maaliki scholar Al-Hattaab commented on the words of Khaleel (“It is recommended for the man in need of marriage who has financial ability to marry a virgin”), saying, “It is forbidden if he is unable to provide for the woman.” [Mawaahib Al-Jaleel Sharh Mukhtasar Khaleel]

If this is the case with the unmarried man, then how would it be for the man who already has a wife and wants to take a second one. Some scholars held that it is better for the man who does not need to take a second wife to suffice with one. Please refer to fatwa 257272.

If you find a woman who would willingly give up her right to the obligatory maintenance and accommodation, then there is no religious impediment to marrying her provided that you are able to maintain justice between your two wives, because one of the conditions of polygamy is that the man must be able to treat his wives equally, as we have previously underlined in fatwas 86818 and 81469.

In any case, your first wife continues to have her rights over you regarding the obligatory maintenance and accommodation and the like.

Allah knows best.