I really love 4-plex due to the ability to use at Short Term Rental (COVID has killed that a bit right now) but there are some loopholes in the city permitting process that make 4-plex a great option and a great way to diversify with STR (Short Term Rental), long term rental, and your own unit as well.

I am afraid that if I try to obtain permit to build something very small (lot is very narrow with set back requirements), the county will advise that septic needs to be re-done (installed 1979).

As your first property, I would actually suggest that you do (if your schedule and lifestyle permits) because the experience you gain while doing so will help you tremendously moving forward in your investment career.  

The engineer should be able to take care of the permitting/applications for this work.Good luck 

Can anyone pull a permit or not?

Cities have rules and neighbors and permits and police.

This creates a tremendous dollar demand which essentially permits the US to add dollars to the system via the Federal Reserve and the banking system and have those dollars eventually be fully kneaded into the global economy. 

Are member permitted to sell their properties on Bigger Pockets?

We discussed the initial process of getting the permits, which I was told verbally it would be a fee of "$600-$700" for permitting + the county fee.

Possibly the township for permits?