since your mother died intestate for transfer of property in your name legal heir certificate would not serve the purpose
2) Legal Heir Certificate is only issued from revenue office of the district to identify a particular deceased persons living heirs.you would require Original copy of death certificate of your mother , affidavit
3) for transfer of property you need letters of administration from district court
4) Mutation is the transfer or change of title entry in revenue records of the local municipal corporation. By mutating a property, the new owner gets the title of the property recorded on his/her name in the land revenue department and the government is able to charge property tax from the rightful owner.
5) you can sell the property in future but better obtain LA from court to confer clear and marketable title to property
6)legal fees vary depending upon lawyer engaged by you