As you probably guessed from the unpaid rent, the tenants did not leave a mail forwarding address that I could serve them court papers at. 

Send it to every address they give you including the current rental assuming it will be forwarded to the address they gave the post office.

Quote from @Eric Winkler: @Tiffany Schumacher - message  me the address(es) please@Tracy Schaffner - message me the address(es) please@Varun M. - thank youHey Eric, I also have questions and also have lack of communication.

I found that the addresses are highly accurate.

I was thinking that the post card thing was worn out, but maybe if one targeted the postcards to reference only addresses that were actively seeking renters on Zillow or Redfin, one could avoid all that waste that comes from blanketing every address in a zipcode. 

Start with the address and details about the rental.Create a section for tracking the lease information.

If they did not provide a forwarding address we send it to the unit address, hoping they filed a change of address form.

What if she lies and claims to have owned a home, or uses a friend's address instead of the rental address?"

It would help if you describe the tasks you want accomplished, then we can address how we handle those responsibilities.

Keep telling me a sob story about her paycheck getting sent to the previous address ( that was 18 days now, not corrected ).- still did not receive the check from the NJ Victims of Crimes office.At this point, I want to file for eviction at the end of the month if she delays the event by 1 day to pay her entire rent ( January and February).My question to you professional is, should I inform her of that decision in advance?