Many properties are held by entities like corporations, LLCs, and trusts. That can make it difficult to find the person or people behind the property. Publicly available information varies from state to state, but all states require every entity to have a registered agent. The registered agent is the person responsible for receiving official notices on behalf of the entity.
How do you find the resident agent? Usually by doing a corporation search on the state's Secretary of State site. It may take some time, but it's best to start with the name of the entity found in the results from your search on PropertyScout.io. You should be able to find at least a name and an address. The next step is to reach out to them directly.