Agree entirely with Christopher Remson's points posted 10/30. If a project is going to go south and one's role in the project comes into question so far as what services were rendered (or should have been rendered), a (hopefully written) agreement and the state's licensing laws are probably the first 2 stops that will be looked into with respect to standard of care.
In Iowa, we are supposed to identify virtually all work product, not just construction documents, a statement confirming authorship as well as professional license credentials. I do so for State Historical Society consultations, master plan/feasibility studies, and concept-level design work. I am practicing architecture when I consult on a historic structure for 6-8 hours, even when the resulting report is just observations and recommendations for the next steps (further investigations and design, usually). This is different from sealing Construction Documents. The states' practice laws vary.
Ultimately, not stamping something doesn't make it amateur work without an owner's reasonable expectation that the work is professional.
As is usually the case, taking the time to educate your client and clearly establishing an owner's expectations very early on is the best way to avoid problems. You don't need to clobber them with a 25-page agreement, but an email or a memo confirming roles and responsibilities - followed up with an appropriately clear agreement - can go a long way.
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Peter Franks AIA
The Franks Design Group, P.C.
Glenwood IA
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