The approval-of-design fling and final sign-off is for the design/zoning/code approval and final use. 

Fines are given to property owners who rent without a permit or entire houses outside of designated resort zones. $10,000 per day of violation, the state wants to increase to $25,000 per day.

And there are a lot of design build and operate companies in LA.

Bottom line, if you want to control costs, and if you want to get multiple bids, pick out some sort of a basis of design a standard that all your contractors can base allowances on.

Regardless of designation, I would see what could be done to mitigate risk of future flooding.

I always hired my Architectural Firm to do some type of design based service, like redesign of a kitchen, or an addition, etc...

I've even heard of some people using their "shop the look" feature by saving down pictures of designs they like (oof of Pinterest, Instagram, etc.) and uploading them to the shop the look platform.

Has anyone gone the route of designing their own website?

I'll say that I'm biased because I'm in architecture and design, and having gone through the process of designing and building an ADU in LA a bunch of times, I know how much work they can take, especially for people who care about design or who haven't gone through the ADU process before.

Do yo know how much of that cost is due to cost of permits, cost of design features that are a result of extremely strict building codes?