Zillow is, as others have stated, a business model based on getting you to their free site in order to derive profits later via other means. 

Occasionally.My business model is 95% referral based.

I have recently become very interested in the wholesale/ flip business model as I am a licensed realtor in Texas.I came across my first wholesale deal this week but I want some assistance as to what would be the best way to handle this transaction.

@Andrew Auger nice model.

Also, I would factor all of the future maintenance with a PM or contractor in the cost model. 

This is a fact that we all have to deal with, however I wouldn't put too much emphasis on it in regards to your business model.

He never set foot in the apartment (saw a model) because when he looked at it the tenants were still there and it wasn't going to be available until the day he moved in. 

I am looking for a 4 Plex Multi-Family with low money down and NOI of around $32,000.I am finding properties where the numbers work if I had the down payment myself as they are worth the investment using that model.

I would check the energy usage on both models and then make the determination.  

Science is about having a model that is verified and refined by experience.