What is the long-term parking situation like at the Anniston, AL depot? I'm assuming from a look on google maps that it would be free and looks like there's several parking spots and also possibly some sort of NS office or something in/adjacent to the depot, so I'm also assuming it'd be a safe enough spot to leave a car for a few days of a trip?
There are 6 Amtrak parking spots on the left hand side of the station. The whole front of the station is used and a county bus terminal so you can't park directly in front of the station. You can most definitely park over a few days.
There are two employees for the bus system on hand during the day and an Amtrak caretaker comes in about an hr or so before the trains are scheduled to arrive. Also NS has an office in the old freight house behind the main station, so someone will always be at the station.
I will tell you that the area directly across the tracks has been known for high crime in the past but has improved. The station was recently remodeled and is in good condition. Originally the whole area was to be redeveloped along with the remodel but the economy put that plan on hold.
Overall I think you would be just fine to parking there long term. Its no more dangerous than parking at a Walmart.