Indian property, NRI owner - how to remove 1/4 share officially

Dear Sirs, Four NRI siblings hold access to a property in Navsari. The deeds have not been altered since it was built in 1980’s by their mother and father. It is believed that only the deceased mother and father’s names are currently on the deeds. The council records do list all four siblings names as the mother and father’s names have been stuck off on presentation of their death certificates. 1) How can we request copies of the deeds from the UK? How much will it cost? One of the siblings ( Sibling A) wants to extract their 25% share by way of agreement and payment from the remaining 3 siblings. The 3 siblings will retain the property and do not intend to sell it. 2) Do the deeds need altering to reflect this change? 3) Is there any tax to pay in this case? If so, what percentage? 4) Is there any legal documentation to be drafted and signed or will a UK agreement suffice? If it is an Indian legal document that requires signing, does it have to be in India or can it be posted to UK? 5) If a signature is required in India, can it be done by someone given power of eterny by Sibling A? 6) If the remaining property owners wish to sell the property in the future after Sibling A has released their responsibilities, will any signature or authorisation be required from Sibling A. 7) Can you recommend any reputable property law specialist in Navsari or Surat that would provide services to resolve the above? Thank you in advance for your assistance.