I started this project hoping i could efficiently review the most amount of properties in order to maximize the potential investment options to bid at auction....this is what I have so far.First thing i did was to create the listings, I matched the properties been auctioned with their corresponding pics and the property specs (rooms, size, floors etc.).Second, for each property I automated the data collection process from public records and created a report with: Foreclosure info, owner info, taxes data, liens including mortgages , satisfaction of mortgages,  assigments, violations and permits and court dockets.This data is updated daily to capture new filings (specially the dockets to capture bk and motions to cancel sales)Now that i have the data i can apply my personal "preferences" to go through the report and in a few minutes discard  properties that have certain attributes I "dislike". 

I'm keeping a Pittsburgh based return address on the postcards/letters, but I'd rather not have a giant collection of returned mailpieces pile up for me to collect on a regular basis.I've heard of an option where the post office can send you photos of your undeliverable mail and then discard it for you, but I can't seem to find anything about this service on the USPS site.

Next, discard the rule and use more detailed estimates (which it sounds like you're doing).  

Your tenant likely discarded multiple bills and late statements. 

If tenant is able to secure help and starts making the payment, is there any legal implication to pay-or-vacate notice or can that be just discarded?

For me that book was written in a different reality, so I discarded that idea, thinking to build wealth with my wage and eventually be able to buy my home... never happened.Some 18 months ago, I came across a webpage in Mexico "ViveDeLasRentas.com" (live from your rents).

While I liked 90% of what they did, the discarding of 10M+ sets of data and then producing vastly differing results clearly points to a problem in the study.

I discarded one of the potential properties I found, and now I am going through a revision process for one property that looks promising.

I decided to send a polite letter with photos to the tenant (who left shortly after the portable washing machine was discovered) outlining my losses not covered and asking for a small cash settlement from them.I thought they would either pay or discard the letter.

You have to constantly be rethinking your plans and changing or discarding them...in this business and I guess in any other.