Websites to Research Owner Phone Number

[Garrett White]

I am building a database of apartment owner’s phone numbers so that I may follow up with them after mailers. For LLCs, I’m researching the Filings found on the Secretary of State page, but am running into the problem that a good many include the number and address of the Property Manager and NOT the owner. What other websites can I use to obtain the property owner’s number and home address? What do commercial brokers use to research owner’s contact info?