You are unlikely to collect a dime, so don't worry about how big of a judgment you can get.

Collect 6-8-12 months or more of rent. 

We use Myrental.com to do all our background checks and collect ID and pay stubs from there.

They're not going to close the deal without the money for current taxes due being collected, so you don't have to worry about it.

We value a long term win-win relationship, well- priced, well-maintained homes to ensure solid tenants as well as respect for our finances and investment, so the PM has to be of the same mindset and ability to perform.This has been by no means passive because things come up that have to be addressed, and a lot has to be organized, optimized and tracked.

Worse, they could put the collection on both of your credit reports, which could show for 7 years even if paid.  

If the state has held a Certificate of Sale less than three years from the date of sale by the county tax collection official, the Certificate will be assigned to the purchaser.

They would not do anything and just collect the check for the sale.

Unless she's breaking some rules, don't do anything but collect monthly rent. 

Any best practices on collecting past due amounts?