I am a Civil Engineer out here at Ellsworth.

Yes, due on sale is a civil or contract issue and not a point of law.If the lender wants the loan paid back they will ask.

It's probably one of the most-litigated areas of real estate, so best to avoid IMHO.  

A civil engineer may be able to help or point you in the right direction.

Now if they are taking your furniture and directing your employees to do unpaid work for them you have a civil case with a potential criminal case against them depending on the laws in your area.

Proof of any service under this section may be made by the affidavit of the person making the same in like manner and with like effect as the proof of service of summons in civil actions.

Subject property is in Oakland and need representation from an attorney specializing in contracts and litigation.

If you're talking about a land survey, call a Civil Engineer. 

If the values were reversed your loss recoverable is $25k and you get a check for that amount.Lastly, keep in mind litigation is the last thing you want as it can take years to resolve.

By then I was at least smart enough to stick to my script ("you and your son need to apply in writing,  I need proof of income,  prior rental history,  civil/background check and criminal background check;  and please understand I WILL verify this information  (this was before seattle outlawed half of this)  -  we went back and forth for several days after the initial showing with her claiming I had agreed to rent to her, then offering to pay cash in advance and such.