Sean Black, co-founder and CEO of Knock, talks about his announcement to take the company public in 2020. Knock allows homeowners to sell or trade in their home for a better one.

Black says the company decided to announce its IPO plans two years in advance thanks to his affinity for the NYSE. The NYSE also reserved Knock's ticker symbol: KNCK.

Black says the difference between Knock and a competitor like OpenDoor is that Knock will help homeowners purchase their next home, while OpenDoor will not. Black says OpenDoor also charges fees on top of the usual 3% for brokers.