Architect is a Search the List category, for members to find well-rated and reviewed architects - be sure to find one with experience in retroactive permits, because some government agencies just charge you twice the normal fee as penalty (and sometimes will take mercy on yuou if it was done by a previouos owner), others can get real nasty or impose large penalties if the application process is not done by someone experienced in dealing with them.
Whether they will require you to tear into ceilings and walls and such so they can see at least a representative sample of wiring and plumbing and such depends on the building department pholosophy and sometimes the individual building inspector's whim. Sometimes for sewer lines they will accept (in lieu of opening up walls) being there to observe while a sewer camera is run through all DWV lines so they can see the configuration of the pipes and that traps and vents are correctly in place - a few hundred to $500 range for that can commonly avoid much more in tearing holes in interior finishes and then repairing them. Of course, the more exposed the piping and electrical (say in crawlspaces or unfinished basement) the easier it is for them to inspect the already done work.
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