I could care less because its not harming the driveway.  

They play loud music, use alcohol and other substances, are generally loud and sometimes even have cookouts.

The plaintiff suffered some degree of injury, usually economic harm   How to avoid all this?

Worse off they could say it harmed their health and was hazardous. 

No harm in checking it out.  

In advance, you are not the best or most suitable replacement, you have no experience or background, so that would do more harm than good.

There will be some properties whose owner(s) are incarcerated, or suffer from substance abuse, severe mental or emotional issues or just don't want to be found. 

I know you're eager to get started but you don't want to cause harm in the process, do you?

I can't help but think that landlords that don't allow pets are really limiting their pool of renters and that an extra month or two of vacancy would do far more harm to their bottom line than potential pet damage.  

Unadvisable.If this is just an exercise to practice evaluating a potential purchase, then there is no harm done, but I wouldn't recommend putting any money on the line at this point.