All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If the matter is as you mentioned in the question, then your brother is extremely wrong, may Allaah guide him. Hence, you may take the matter to the court -if there are Islamic courts in your country- so that you would get your right from the inheritance. If there are no Islamic courts, then you may take the matter to anyone who is able to oblige your brother to give your right to you. However, we advise you to forgive him and reconcile with him and advise him to repent.
The following matters should be mentioned:
1) The custom in your country -which you mentioned- that a person who rents a shop for a long period does not leave it unless he takes its value in the market price, if this is stated in the rent contracts and the contracts do not specify a limited period when the contract comes to an end, then this is not permissible. This is not permissible because such contracts are not valid and it is an obligation to give back the rented property to its owner. One should not rely on man-made laws in rent contracts, as they are not in concordance with the Islamic Law because it makes the rent contract eternal.
2) It is not permissible to accuse your brother of doing magic to you just out of suspicion; you must have clear evidence about this. Allaah Says (what means): {O you who have believed, avoid much [negative] assumption. Indeed, some assumption is sin}[Quran 49:12].
As regards the will, you did not clarify to us its nature so that we may give a religious ruling about it.
Allaah Knows best.