Final answer:
The amount of the boot is the property's fair market value.
Step-by-step explanation:
In a like-kind exchange, if non-like-kind property is received as boot, the amount of the boot is the property's fair market value. For example, let's say you exchange a piece of land worth $200,000 for a building worth $180,000 and receive $20,000 in cash as boot. In this case, the amount of the boot is $20,000, which is the fair market value of the building received.