We begin by clarifying a few points. Firstly, in an actual case, we cannot give a definitive answer without hearing both sides. This is not only a procedural matter. Details, which either side may overlook, can surface during a joint discussion in a way that influences a ruling. Secondly, it is best for the sides to work out the matter between themselves. In that context, it is worthwhile knowing the halachic guidelines. Upstanding Jews should use them as the point of departure when trying to arrive at a fair solution that satisfies the basic needs of those involved. It is in this spirit that we provide the following information.
When two or more people inherit an estate, their relationship is like that of business partners in regard to most considerations, including the right to end the partnership.[1] One difference is that people’s agreement to enter a joint venture for a set time may include an obligation not to break up the venture prematurely.[2] Because inheritors become partners as the result of a common relative’s death, not by an agreement, and for an open-ended period, each has the right to terminate the partnership. The question is how to go about this in a given case.
The optimal way to terminate a partnership is to divide the property proportionally among the partners. However, there is a feasibility check on that arrangement.[3] Each side must be left with a portion that can be used for the same function as the entire unit was. The smaller parts must be similar enough to the original property to be called by the same name. For example, the divided parts of a field must be identified as fields and not gardens.[4] Living quarters have to be broken up into sections, each of which could be called a home and would be suitable for use as a complete dwelling.
Where halacha does not deem it feasible to divide the property, the next best system is known as gud oh agud.[5] This system, which is the subject of an Amoraic dispute in Bava Batra,[6] means that Shimon challenges Reuven to either buy Shimon out or allow himself to be bought out by Shimon. The Rama[7] even allows Shimon to challenge Reuven with an amount higher than the market value. If Reuven does not want to pay more than the property is worth, Shimon is given the opportunity to buy it at that higher price. However, if Shimon is not capable of buying it, he cannot force Reuven to buy him out.
When neither side is interested in buying out his partner and the property cannot be divided feasibly, two systems remain. The preferable one is to rent out the property to a third party and divide the profits.[8] Where the property does not lend itself to being rented out, the two can time-share its use. In the case of living quarters, they each get intervals of one year.
Each of these alternatives has particulars that determine if and how it should be carried out. We do not have enough details to provide you with an exact course of action. We suggest that you use the above guidelines to help you arrive at a mutual agreement. If, as it sounds, the property can be broken up into two living units in a practical manner, then if one of you prefers that arrangement, that is what should be done. A cannot force B to buy the house if he does not want to for whatever reason. Renting it out is halachically and probably practically a better idea than time-sharing.
If you cannot reach an agreement, it is perfectly respectable to go to a beit din to examine the claims in detail. It is regrettable if siblings reach the point of anger and recriminations before ending up in a beit din. One might prefer the more intimate forum of a rav knowledgeable in monetary law than a formal beit din.