All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
In principle, it is an obligation to be just when gifting the children according to the most preponderant opinion of the scholars, but if the father favors one of his children by gifting him and not gifting others for a sound reason, like because the child is dutiful to his father and that he takes care of him, then according to a narration from Imaam Ahmad this is permissible because this favoring was for a sound reason. This was cited by Ibn Qudaamah in "Al-Mughni". For more benefit, please refer to Fatwa 123559.
On the other hand, if your father wants to distribute his property during his life, then he is permitted to do so but he has to be just between you, for example he should give the female the same as the male and he should not favor the males over the females because the distributed property in no an inheritance.
If he favors one of his children by gifting him/her and not gifting others for a sound reason, then this is permissible especially if the remaining brothers and sisters agree to favoring him/her. Indeed, there is no Sharee’ah limit for this but he should not wrong any of his children or treat him/her unjustly.
Also, there is no Islamic limit for what the father leaves for himself. He is permitted to leave whatever he wishes and not distribute anything at all from his wealth, and he is permitted to distribute his entire wealth amongst his children. The matter in this regard is easy, but it is better if he donates some of his wealth, like one-third or less, to the poor and destitute as charity, and if he puts that in a continuous charity, like an endowment and the like, then this is better for him so that its benefit will reach him after his death.
As regards the method of distributing the land and the estate which is built on it, or whether the father needs to estimate the value of the house before its division, then there is no specific text in this regard. What should be done is to attain justice in the division in a way that each child gets the same share like the other.
Allaah Knows best.