You find this out by talking to people, speaking with past residents, people in the industry, or mystery shopping the property.Using technology to pull in data so you don't have to manually type it in, is helpful, but other than that, I would not trust automation. 

I found a listing in Northern California on Zillow that is vacant land with approved plans for building a home.

This is where the substitution clause comes in, as I understand it.

I’d love to hear any tips or strategies that have worked well for you in real estate marketing, especially with PPC campaigns.For those who’ve done this successfully, are there specific keywords, ad placements, or campaign types that you recommend?

I feel that you should have about 30k-80k in equity ($250k-300k property value) based upon the little bit of information you have told us and my experience in palm bay, FL / Brevard County, FL.

Hi Franklin, glad to have you as part of this awesome community! 

Most investors from California that post stuff like this usually end up in the Midwest.

At this point I'd be more likely to hire someone as a consultant, if that sort of arrangement is a thing. 

However, I haven't been able to find any official information confirming whether this is legal or if it violates any laws.I'm hoping someone here might have experience with this or know of a reliable source that can clarify the legality of contacting a tenant's commanding officer.

There were a number of years in this market where it was absolutely possible to cash flow a duplex with the rent from one side.