It starts with "Like-Kind" Properties.
Any real or personal property can be exchanged, provided it's held "for productive use in a trade or business,"
or "for investment," and is exchanged for property of like-kind that will also be held for one of these same purposes.
Most real property is considered "like-kind" to other real property. A single-family rental unit, for example,
may be used to acquire another like it, or to purchase a warehouse, retail center, or office building. Like-kind
limitations on personal property are more restrictive; assets must be classified similarly under government accounting classifications.