Is probation needed for my fathers WILL

Hi Sir, My father has passed away 10 years back he has registered a WILL for the property he had bought / owned and mentioned the rights of percentage for my mother / brother / sister and myself ( 4 legal heirs) Now my mother passed away recently. My question is if it is required to probate the will necessarily in these three situations.. 1) we three may plan to construct house of one floor each at the said property 2) two of us would take possession of property and settle on person as per the guide line value and construct two portion of house at same plot for 2 3) one person settle the value according to the guideline value to other two persons and construct / own a house at the said property plot Should we need to probate the WILL or internal settlement deed signed by relevant persons in all three cases would be sufficient to have the other person the marketable title of that property if is is done without probating the WILL and please let know the cost of probation according to Madras High court jurisdiction as our property comes in chennai corporation limit