I'm bringing the team: architects, designers, planners, builders, investors, lenders, etc.

Check with your architect for requirements as to location, but it would need to be accessible for reading, either directly by you/your property manager, or possibly by the tenant.

I'm using a General Contractor but wondering if this type of thing would normally require an architect even if it's of the utmost importance that I do not do anything to the house that would require building permit/approval.

Why would someone go through the trouble of hiring an architect and drafting the plans and then not build?

Hire an architect to help you navigate through all of the above 

It would be good for you to look into building an ADU above, I can connect you with an ADU designer/architect for confirmation. 

Good morning BiggerPockets family, I want to introduce my interest in being able to work with someone or with a company in the area of ​​flipping houses and to be able to contribute and learn from this beautiful work, contribute my experience as an architect,A challenging position where I can use my academic and professional experience as well my leadership and bilingual abilities in inspection y/o supervisor architectural.Thank you.

I also wanted to know what the average cost of architect plans are.

The way I would pursue resolving this is to find a local architect familiar with your jurisdictions fire, life safety, egress and accessibility guidelines to help you develop or demonstrate a plan for the property.

You'll also need to consider permitting, architect, engineer, possibly zoning...etc.