When you do your next one, the trick is to make sure you can evaluate the costs BEFORE you ever buy it.  

All of my LOs as the Optionee have been from sudden sellers (sudden job transfer, divorce, health, default) of pretty houses with low equity.I didn't do any of the tricks you mentioned, but they weren't listed on zillow or wherever either.  

The trick is finding the right match.

I trick I use is to find a comparable property I like and then look up the contractor associated with the building permits in the county or city's permitting system.

(ah, so paid answering service given the script "this is zillow" I use one as well for my business accept that the service pretends they are in my office referring the call to me instead of pretending to work for a totally different company in a bid to trick the caller). 

I am sure there will be a few tips, tricks, resources or ideas that you hadn't heard before.

The email I received was strange as though the person was trying to ask me a trick question, so I looked him up.

Is there any advice or tricks to getting better results?

It is not difficult to serve a deadbeat tenant; there are numerous tricks to get a tenant's new address (some discussed on BP) if you have done your due diligence upon on boarding and collected enough data on this person during that process. 

One trick we use sometime is take a water hose from the back of a washer machine...