He built a house and gave it to his wife instead of her dowry, and he lived in it with her; is it part of her estate?
Question

                We are 3 sisters. No brother. My father had built a house in his life which he had gifted to  my mother as a dowry. (note: The original amount of dowry is much lesser than the worth of the house). This is a multi-level house in which we used to live throughout our lives. And my father used to rent a portion of the house in order to receive extra income.

After the death of my mother, my father had been told by the Imam of local mosque that the way he gifted the house as a dowry is not acceptable in Islam. A dowry is something which you pay to your wife and she is the sole proprietor of that. But in this case, as my father with all family members (including parents and siblings) been living in the same house; the purpose of the dowry has not been accomplished.

So, to compensate, he was advised to pay the amount of dowry to any Sadaqa e Jariya on my mothers name. But as my father was very sick and financially weak, so he didnt pay and told us (daughters) to pay that money as Sadaqa whenever we would have sell the house and get the money for our mother.

Meanwhile, as the house was on my mothers ownership, so after her death it was transferred to the legal heirs ( i.e. my father and we 3 sisters).

Now after my father's death we are confused, as to how should we distribute the shares. As according to Shari Law, due to  not having brothers, our Uncles and Aunts are eligible heirs too.

Should we consider this house as my mother's property or my father's property?
Praise be to Allah.
	What we understand from your question is that your father 
	gave the house that he built to your mother instead of her dowry that had 
	already been decided, and he registered the house in her name. This means 
	that ownership was transferred to her, whether she took possession of it or 
	not, because this does not come under the heading of a gift; rather it is an 
	agreement on an exchange and it comes under the rulings on buying and 
	selling, and buying and selling becomes binding when the deal is concluded.

	It says in ar-Rawd al-Murbi‘ (p. 248):

	If he comes to a deal to give him his due in a form different 
	from what he owes him, such as if he acknowledges that he owes him a 
	particular item or a debt, and he gives him something in its place that it 
	is permissible to give him instead – so that if it is one currency instead 
	of another currency, which she can then exchange, or if he gives him an item 
	that he can sell, then it will be regarded according to its value.

	Ibn Qudaamah (may Allah have mercy on him) said: 
	

	Transactions are of four types, one of which is a binding 
	contract when the aim is exchange, which is like buying and selling, and 
	whatever comes under the same heading.

	This is of two types, one of which is that in which two 
	choices may be stipulated: the choice to proceed or annul in the same 
	sitting, and the choice to stipulate a condition, which is applicable in 
	cases where there is no stipulation to do the exchange in the same sitting. 
	Making a deal comes under the same heading as buying or selling, and a gift 
	in return for compensation also comes under this heading, according to one 
	of the two reports, as does renting.

	End quote from al-Mughni (4/130).

	It does not matter that he and his children lived in it, or 
	that he was in control of it and rented out part of it, because that would 
	have been done with the consent of his wife when she allowed her husband to 
	use some of her property.

	Based on that, it is part of her estate; your father gets one 
	quarter of it and you (sisters) get two thirds. Then we should see if she 
	had any male relatives on her father’s side, such as a brother or brother’s 
	son, or a paternal uncle or paternal uncle’s son, in which case the 
	remainder goes to these male relatives. If she did not have these male 
	relatives, then the remainder goes to you (sisters) only, not to your 
	father.

	If your father dies, then his estate is to be divided among 
	his heirs, and one quarter of the house is to be included in his estate. So 
	the daughters take two thirds, and the remaining third is to be shared 
	between his full brothers and sisters, with each male getting the share of 
	two females, because Allah, may He be exalted, says (interpretation of the 
	meaning):

	“if there are brothers and 
	sisters, the male will have twice the share of the female”

	[an-Nisa’ 4:176].

	And Allah knows best.