These cases are very common in various Courts of India and Supreme Court of India. I can understand your concern in this regard.
Please note that Hindu Succession Act was amended in 2005 and it gave equal rights to the daughter in terms of property. Prior to the Hindu Succession Amendment Act 2005, sons enjoyed rights over the deceased father’s property, whereas daughters could do so only till she was unmarried. It was understood that after marriage, a woman attaches herself to the husband’s family and therefore, has rights in another Hindu Undivided Family (HUF) altogether. Now, married and unmarried daughters have the same rights on their father’s property as their brothers. They are also entitled to equal duties and liabilities as their brothers. In 2005, it was also ruled that a daughter has the same rights, provided that both, father and daughter, were alive on September 9, 2005. In 2018, the Hon'ble Supreme Court stated that a daughter can inherit her deceased father’s property no matter whether the father was alive on this date or not. Hereon, women were also accepted as coparceners. They can demand a share in the father’s property.
Therefore, following is my prima facie view/opinion for your concern:
1. The debts which has been repaid by you can be adjusted mutually or whenever the case is filed and it would be considered for dividing. You can place on record the copies of the Housing loan contributions from your end during and post your father's death. Court would consider it.
2. She is even liable to share the expenses of the mother.
3. For your sister's marriage, your father had sold his properties. It would be considered for dividing.
4. For the second property which you have built on your own, requires detailed discussion with complete property documents.
You may contact my secretary to connect with me for clarification.
Gopal Verma
Advocate on Record
Supreme Court of India