Just for clarity... in my state (WV) any activity where I sell someone else's house could potentially be considered a professional real estate transaction requiring a Realtor license. 

It’s kind of like Mint.com on steroids with much greater detail and much better features.  

Zillow shows that we have about 500% more views than all the other houses but that might just be because we are the only ones that took professional photos.

It is a way to find current contact info and whereabouts from old/incomplete contacts and whereabouts.When used by a Real Estate professional "skip tracing" refers to obtaining phones numbers from name and address info of property owners. 

Or it can only be used for professional cleaners?

Brokers' poor reputation has caused many brokers to rebrand themselves as “Commercial Real Estate Advisors” or “Real Estate Consultants.”This is similar to the Wealth Management and insurance industries, where commissioned salespeople pretend to be professionals who always keep the client’s best interests in mind.

With home prices hitting all time highs, I was wondering what experienced real estate professionals' perspective on the Silicon Valley market was?

There are investor-focused agents and other professionals that can help. 

But, they each seem to lack some features the other one has. 

In other words, all industry related professionals would be good deal sourcing points.