Things to consider: know the area (it sounds like you have an idea as to the area as you had gone to college there but it's good to reacclimate yourself with it in the event areas have changed for better or worse).Also, know local laws, taxes, inspection procedures. 

Personally, if it were me, I would invest in 15 minutes of a tenant/landlord attorney's time to make sure you're clear on the procedures that need to be undertaken.

AFTER the tax sale, the prior owner must go through a myriad of procedures to challenge it and they must have a legitimate reason to do so (like they actually paid all the taxes before the sale but the sale accidentally still went on, the sale was improper, etc). 

Could someone with experience expound on the procedure for any of us trying to learn?

Starting with firing your PM and then deal with the tenant as your attorney advises.When you are looking to hire a new PM, have your attorney draw up a contract that defines the nature of the relationship you hope to have with the new manager, and ask to see a copy of the PM's Policies and Procedures Manual. 

If you want to deal with flea then you need to use the right flea control procedure to work.

That’s a local state dictated procedural question.

This is the proper procedure to follow and is designed to protect the landlord in the event that rent does not end up being paid.

You should implement your Week One procedures first. 

Bottom line is you can jump through hoops to insure your HOA follows the proper procedure so they can legally enact the new regulations or you can move on when your tenants lease is up.