Inheritance property dispute - suggestions requested

This question is in relation to my mothers shared in her deceased mother’s house in karachi, she passed away 10 years ago.

my mother has two brothers, elder brother is living with his family in this house. Younger brother is of unsound mind (classified as minor or insane)and he is single and lives with the elder brother under his care.

elder brother is not willing to give my mother her share in property, even though he has the means to do so.

elder brother has indicated he might give her the 20% share if she agrees the rest is kept by elder brother, as younger brother is a minor and cant have property under his name and will be safeguarded by court. My mom does want to ensure any share due for younger brother should be in his own name. Eventually younger brothers share should be distribute according to sharia, that is 1/3rd to my mother.

do you suggest going to court or settle out of court? If this is done through court, will we be able to get full market value of property? Or is it done at official values in court? If we go to court is it a better option to safeguard share of younger brother?

they have been living there for 10 years and my mom has been demanding her share for this long, can she claim rent on her share of property occupied by them, would a court accept it?

have spoken to a couple of lawyers, they all say do a case, but not clear on what value will house sell through court and what is best way to get our full share, i feel lawyers want to make their fees without being totally open on details of how it will work.

if anyone knows any good experienced inheritance lawyers in karachi, please share the names.