Anything that involves a load bearing wall will generally need an architect IME, but it can also be required (maybe indirectly) through the jurisdiction's building code/enforcement.Got it, thank you for lending your expertise!

Germain Depository Institutions Act of 1982. 

Wind stone Private Lending?

Without going down a rabbit hole here and overwhelming you, there are also creative ways to buy properties without needing to get traditional lending, but these types of deals are harder to come by and usually come with more risks. 

Lenders will lend the lower of the amount between LTC and LTV.Do you require an appraisal and survey?

The only way I see a low or no-money-down scenario being viable is if you have a lender willing to lend based on the Loan-to-Value (LTV) ratio, and if you can find a deal where your total costs are low enough to keep the LTV within the lender’s limits. 

Lendbase, as a "correspondent lender" basically shops for and lends other Lender monies.

Loan Origination Systems (LOS): What works best for mortgage and private lending?

We use it for private lending.

HELOC are great for short term lending.