Are the brothers to be given their share from the value of the first sale, or do they partake in the new sale of the house? And is zakat due on real estate, whether sold or not, knowing that I no longer reside in it?

If you bought a house with your own money and explicitly declared that your siblings are partners in it, and they accepted, then this is a donation from you. The house then becomes the property of all of you and its price is divided according to Islamic inheritance law, and you are not permitted to retract the gift. However, if you did not utter words indicating a donation and merely intended it, then you are not obligated to include them in what you purchased from your uncles' shares, but they are your partners in their share from your father. In this case, if the house is sold, you all share in what corresponds to your father's share, and you exclusively own what you purchased from your uncles' shares. Zakat is not obligatory on real estate unless it is for trade with the intention of profit. If the intention is not trade, then there is no Zakat on it.