Generally speaking the IRS targets high income taxpayers as the big fish offer the highest potential "ROI" for the IRS auditors' time.The question to you, respectfully, is "does it matter"?

Do a quick title search on the county recorder/auditor site

In its audit guidelines, the IRS instructs its agents and auditors to check with the chief counsel’s office for guidance.

However, despite all the documents I have for my property, along with assessor/auditor internet resources, I am having a difficult time finding a map which accurately depicts my property line.

You could check your county auditor's website for a property search function. 

The auditors/property tax office, or assessors office or a helpful title rep could help you find out for sure.

Your County Auditor should have an interactive zoning map...if not, the city oftentimes has this resource...

Taxes are from the county auditor website at 226.19 a year, in a very poor rural area.

I assume CA has county auditors/assessors.

With modern technology lenders and auditors are able to fully audit their loans using AI and machine learning -- rather than looking at a few percent they are able to analyze them all.