Advertising an illegal, non-conforming basement for rent, whether publicly or privately, out right violates local laws. 

I would just point out that you must make clear you are selling the interest to purchase, cannot advertise the underlying real estate (as that would require a license).

(I also suggest an in person visit to meet folks and get to know the areas, not to see a particular property but to build relationships.)Once you are active in a market you will start to connect with investors who may be selling, wholesalers who have assignable contracts, and your realtor may also have access to off market opportunities. 

You have a couple ways to access that equity.... you can 1031 your orange county property into a large multifamily and create cashflow that way.

They can provide personalized advice and may have access to loan programs that suit your needs.

Of course, if you have access to leverage that works, the deal will be even better so read on.b.

@Jake HughesMore experienced investors may have access to Private Money.

Under $150, easy to install and use, tenant can set their own code but landlord can retain the master and always have access, tenant can't lock themselves out, standard key for emergency backup, batteries last a couple years, etc.

Advertising (photos and listings.) turn over costs, snow removal, and those kind of things.

Go to Etsy and search for "rental property tracker," and you will find hundreds of nice spreadsheets to track 10-20 rentals, usually for under $10.Software has extremely helpful features like online payments, marketing syndication (click a button, and your property is advertised on multiple sites), electronic document review/signing, maintenance tracking, and owner reports.