1. The property was owned by your father who did not make a will in respect thereof during his lifetime. So after his demise his widow and all his children succeeded to his house. Division can take place amicably by drawing up a deed of partition or family settlement. If your sisters are willing to give up their share then they may execute a deed of relinquishment.

2. So far as the properties in the name of your mother are concerned, she can execute a will or gift deed to transfer the properties to you and your brother.

3. Stamp duty in your case will be 4%. It cannot be avoided even in case of gift among blood relations. Registration charges will also have to be paid. Will is a better option if you wish to avoid payment of stamp duty.

Case 1. Since your father has died intestate(without writing a WILL), the property would devolve equally to his Widow and all the 4 Children. However since you have stated that both your sisters are willing to give NOC in favour of their mother and two brothers, your sisters can execute Relinquishment Deed in favour of their mother and two brothers. Alternatively, they can execute Gift Deed in favour of any one or all other beneficiaries. Regarding Stamp duty it is minimal and differs from State to State and for this better consult a local Lawyer.

Case 2. During your mother's life time, she can gift the property to you and to your brother by executing Gift Deed.

1. You can make a settlement deed for your deceased father's property wherein your sisters also apend their signatures duly relinquishing their rights on their deceased father's property in favour of three of you,

2. Similarly your mother also can execute a Will or execute and register a settlement deed for the properties standing in her name,

3. Will is not required to be registered mandatorily. It attracts negligible stamp duty for settment deeds which depends on the value of the property,

4. The Registration amount varies from state to state,

5.it your local Registretion Office to ascertain the value of the property, Registration fee etc.for the settlement deeds to be signed in connection with the said properties.

1)case no 1 . on your father demise you have 1/5th share in property standing in name of your father . your 2 sisters can execute relinquishment deed/ gift deed to relinquish their share in your deceased father property .

2) case no 2 :your mother can execute will or gift deed in your favour or your brother favour .

3) some states like Punjab, haryana have exempted stamp duty for transfer of property by way of gift deed in favour of close family relative . as far as Delhi is concerned local lawyer can guide you in this regard

For case no 1, it is better you have to execute partition deed amongst family member so the stamp duty payable to state is very nominal.

For case 2, it is better execute gift deed from your mother so there shall not be a worry for tomorrow and if the will is executed by your mother and any of your brother or sisters has challenged the will then you are in trouble and will is always suspicious document.

A. Case No. 1: You can enter into the Registered Partition Deed between all the family members or you can obtain Registered Release Deed in respect of your sister share. The stamp duty variable to state to state.

B. Case No.2: Gift Deed is the better option to transfer the share of your mother due to stamp duty will be very less within the family. I Wouldn't recommend the Will in you case because it will be effected after death of your mother and the will need not be registered and probate is not compulsory in your region.