Well, yes--and no! I'd definitely insist upon having a septic system inspection done but I'd pass on letting this inspector do it! There's just no way a system can simply "look okay" unless a minimally thorough septic evaluation is performed. And while a septic system inspection is not a required part of a standard home inspection, any home inspector offering that service has the responsibility to do it right or not do it at all.
In my home inspection business, most of the homes we inspected had city sewers. In the occasional house that had a septic system, I regularly declined performing this additional evaluation, preferring to leave that up to the folks who did them all the time.
For a state-of-the-art look-see into what a present-day septic inspection should entail, I turned to Joe Corsetto, past president of the American Society of Home Inspectors and a registered environmental health specialist with the State of New Jersey. Joe says that dye testing is inadequate in almost all situations, except near water when it can help detect a leak into the waterway. He recommends that a thorough septic system inspection include the following four steps at a minimum:
Each septic system component should be located and opened to perform a visual check of its function. This is an absolutely essential element of all thorough septic inspections.
The gravel disposal field, laterals, seepage pits (older systems) and other elements must be probed to determine the presence of abnormal saturation. The home's plumbing system must be run enough to simulate usage (known as volume loading).
Inspectors should perform a record check at the municipal Health Department. This can help identify all sorts of concerns including proper permits, plans, complaints, etc.
A septic system inspection as described above should cost between $450 and $650, which, while significant, can help you avert repairs costing much, much more.