I'll give you the high level steps I'd take in your case:1) It's great that you don't advertise exactly how much you have.

You won't see investor interest, no matter where it's advertised.

Zillow is basically and advertising company to sell buyer, seller leads to realtors, not as a Sale Platform. 750 views are mainly because the listing has been "crawled' by other search engines for indexing purposes. little to no customer support.

The vendor or contractor gets  income w/o additional advertising and also more referrals down the road. 

I use Cozy.co .Websites would typically be for advertising large complexes or building a brand. 

How do you advertise your vacant units?

* How do you advertise your vacant units?

Zillow is an advertising company, not a real estate broker or an appraiser.I've seen properties with a "zestamate" in multi million dollar neighborhoods listed in the 200K range.

I put RE on the back burner to focus on school and making new friends.Unfortunately for me, because I was only accepted as a transfer, and because I lacked a significant number of prerequisite classes for other majors, I was forced to choose between Advertising or Public Relations majors in the College of Journalism.

Asset managers frequently supervise other property managers.The individual building manager may be employed by a property manager or directly by an owner, and usually manages a single large property.The resident manager may be employed by a real estate broker or a managing agent or an owner to manage an apartment building on a part or full-time basis.Essentially, a broker's license is required if you do any advertising, leasing or collection of rent.