This part applies to all real property loans, and all lenders making such loans, as those terms are defined in § 591.2 of this part.§ 591.2 Definitions.For the purposes of this part, the following definitions apply:(b) Due-on-sale clause means a contract provision which authorizes the lender, at its option, to declare immediately due and payable sums secured by the lender's security instrument upon a sale of transfer of all or any part of the real property securing the loan without the lender's prior written consent.

Follow the proper procedure defined in the agreement. 

A simpler solution may be to make a gift (as defined by IRS) or no- or low-interest loan, but this way loan is backed by house and my mom is able to capitalize on lower rates for the mortgage.

Speaking in broad generalizations here but if you are planning on building a house in a residential zoned area and your site meets the water, sewer, garbage, electricity requirements you shouldn't have a ton of trouble with the jurisdiction in building something to code.

He's the person that needs to be convinced.3) Don't trust anybody who makes broad sweeping generalizations such as "never invest in real estate".

Standard HELOC or 2nd is way safer and defined. 

I would definably refinance.

On the other hand, this recession is not being caused by poor standards, or greedy businesses or over investing, (Animal spirits as our current economic system would define it).

I did a future pricing expectations episode (episode 3) on my youtube channel - the owner's surveyed said they were expecting most deals to transact between 5-9% cap and that's fairly consistent with what I've seen in the marketplace.Also, this is an extremely broad metric (meaning that it could differ greatly depending on region and how COVID 19 has affected the area), the owners surveyed were anticipating a 15-25% price drop as a result of everything going on.I haven't actually heard prices dropping yet from the broker /owner / industry convos I've had - but it's something to think about as you try to price future purchases.

More companies and employees will likely be open to it.Of course, this is a broad category but I truly think there will be opportunities there.