Is the grandfather's oral will of an apartment to his grandson valid and enforceable, especially with witnesses present and the heirs refusing to acknowledge it and selling the building, including the apartment, without the grandson's permission? And does the grandson have the right to demand the value of the apartment which he deems fair?

The will is executed if it is proven by the testimony of two witnesses and the heirs do not contest it, provided that it does not exceed one-third of the estate. If it exceeds that, the excess portion depends on the heirs' approval. Whoever delays or alters the will commits a sin. Ownership is transferred to the legatee upon their acceptance of the will after the death of the testator. Based on this, if the legatee accepts the will and the apartment does not exceed one-third of the estate, it becomes the property of the legatee, and the sale of it by the heirs is void. The legatee must be compensated with a similar apartment or its value. The legatee has the right to claim their right and refer the matter to the judiciary without severing kinship ties.