I want to start expanding our business by acquiring more properties, but I don't want to rely on just the MLS.

BPOs rely on agents who get paid little ($50-100) to do the work, so usually its half assed work.  

Btw, caulk alone should never be relied on as  the primary method of protection against leaks.

The man had a stroke several years ago and has relied on his wife to take care of him for the past ten years or more (including the finances).

I just want to warn you off of relying on Zillow except for the most general info like sq. footage taxes etc.

Another problem was that I was new, largely self-taught and had very few tools from which to rely on or skills of exoerience, to be candid.One of the best skills I gained was the confidence to walk away from marginal deals and not waste time on unmotivated principals. 

You can do this and you wouldnt have to be relying on a system like Zillow or some big hosting site with lots of other competitors.

Can't post directly as per forum rules.You have to be careful of over relying on this kind of data.

Another buyer comes a long and I provide the report which they rely on that may be inaccurate. 

Interest only isn't a good way to finance long term RE holdings, you're relying solely on appreciation to establish equity.