Septic systems are as important as wells and they too can be very expensive to repair or replace. A septic inspection should tell you whether the system is the appropriate size for the home, whether the tank and other components seem to be in good condition, and whether the system seems to be functioning properly. The answers to the first two questions should be relatively straightforward, though there are components of the system that simply are not accessible to any inspector. It can be much more difficult to tell whether a system is functioning properly unless the malfunction is serious. It may be impossible to say whether a system that is working fine for the couple currently living in the home will continue to function adequately once you move in with your family of six.