Government Programs Look into local government programs or grants designed to help property owners with essential infrastructure repairs.

So, your issue is with the county government based on what you just said because a home built by a licensed contractor would also have not been inspected.I'd be JUST as concerned about a contractor built home with no inspections as I would a homeowner built home with no inspections.

where I do think it helps is if your raising money from folks and or with banks..MBA gives some credibility for sure..

You could reach out to Kevin Kim at Geraci LLP in CA who's firm does securities and PML law in all states and is intimate with CA, OR, WA, and ID laws as well as corresponding state specific financial institutions governance (in WA it's called DFI or Department of Financial Institutions) and how to navigate their expectations accordingly... 

I think the best approach is to have a free and open fast search engine that organizes all the delinquent property lists across all the 3,000 counties and links back to the Source of Truth at the government site.

., then the website is a point of reference, but isn't as important as the experience and credibility you give off when talking with owners/real estate investors. 

How do I check the credibility of a lender?

Focus on credibility, focus on value and construct an accurate avatar of what a motivated seller is, and once you do this the answers will be right in front of you.

I should explain that our little outfit has been investigated in the past by the federal government, due to our own stupidity, and so we also cooperate extensively with a few agencies today in our operations.

Building ADU , cynically, is like we're subsidizing California government for housing problem that they're created lol but that's my personal opinion.