It is possible to complete the inspection in one day, type up the report that night and have it ready the next day.  The most convenient way to get it to you is to email it.  This is handy because you get it quickly, but also because you can forward it on to your realtor and ultimately to the closing attorney.  In general, I need more than one day to do the research that is needed.  A better question is "How long will you have to wait for the original inspection?".  I specialize in fast service.  I try to get to your house for the interior inspection either the same day that you call or possibly the next day.  It is important that you get the Title V inspection done as soon as possible.  Hopefully, you will have it done before you list the house with a realtor.  In the off chance that you have an expensive problem, you may want to adjust your price, or make the sale contingent on splitting the cost of a new system.  In either case,you don't want to hear bad news and have the buyer decide not to buy your house.  Do not pump the septic tank before the inspection.  The Board of Health will reject the Title V if the pumping report shows that it was pumped before the inspection.