Property own by 2 people each own 1/2 interest

Property can be co-owned in several ways, the 2 most common being: "joint tenancy" or "tenants in common". Basically, in either case, any of the co-owners can sell off or give away their undivided interest. The big difference being if one joint tenant dies, their share is divided equally among the other owners instead of going to their heirs (this is known as "rights of survivorship"). Whereas, with a tenancy in common, an owner can bequeath their property to whomever they choose. So a co-owner could in theory sell just their share of a property, however it would be difficult to find someone who wants to co-own property with a stranger. Typically, the procedure by which co-ownership is terminated is called “partition”. This is the legal tool employed by courts in situations when co-owners of property cannot agree as to ownership matters. Partition allows for the division of the property among the owners (any co-owner can file for such an action). Accordingly, if a property can be physically divided a judge will instruct that it be done. However, if division would be impracticable (such as in the instance of a single family house), a court would order a sale in lieu of partition with an equitable division of the proceeds among the co-owners. Before doing, the court would permit one co-owner to purchase the interest of the remaining co-owner at fair market value. Since it’s a very detailed process regulated by statute, you’d need to consult with an attorney in your state to get the specifics.