Please contact me anytime if I can be of any assistance! :-)
A septic system, most modern ones anyway, are really simple:
You will have the big tank and two or more leech lines running away from it.
If the tank isn't working properly, that is, enzymes turning solid into liquid, then it can fill up and back up.
If the leech lines are clogged, they can overfolw and the grass above will change color or die.
Maintenance is simple; adding Rid-It or Yeast regularly; you need it to be "regular".
An inspection will dig up the cover to look at the levels in the tank.
Yes, it is a very good idea when buying.