Wells Fargo ultimately turned me down because my specialist was completely clueless in general, and because she failed to accurately relay what I was telling her to her "internal contact" on the phone. 

I would still work with a title company on this and let your lender know (if you have one) of the name change and what you are doing so they do not think you are selling the property.Another option would be to create a living trust for estate purposes and transfer it into the estate.

Therefore, transferring our jointly owned investment property into my SMLLC would not trigger a due-on-sale clause?

Alternatives to ConsiderIf you want to involve an entity for liability protection or other reasons, here are some potential approaches:Assume in Personal Name and Transfer to Entity:Assume the loan in your personal name and later transfer the property title to an entity.Important: Transferring title may violate the loan’s due-on-sale clause unless explicitly allowed by the lender.

Most don't have the systems and processes internally that institutions require.  

Too many stories of hacking to get at wire transfers, etc.

Transferring mortgaged properties to an LLC may trigger due-on-sale clauses, but transferring to a trust first can mitigate this risk.

They were called Overhere Management before they changed their name to Zeker due to some internal leadership issues.

They are a new international lender in Costa Rica that offers cash out refis.

@Maegan Quaife, Of the 4 prongs of the Internal Rate of return 2 of them are very high for you - cash flow and amortization of the loan.