You would probably have to partner with someone who has a track record, or at least a reputable GC, in order for a lender to consider you for a construction loan.

Are you leveraging the stability of conventional loans, the speed of hard money loans, the flexibility of private money, the creativity of seller financing, or the collaborative approach of partnerships?

Double check the names, address, loan amount, other contact information, etc A few important documents include: The closing disclosure, The deed of trust, The note, and The warranty deed.

To secure the construction loan for the duplex, I would use the entire property as collateral to meet the down payment requirements.Does this sound like a good strategy?

If you time this well, and develop mid-late Recovery phase, your projects should be coming online right at the height of the demand depending on the market.

Fees on DSCR loans always depend on closing date and loan amount.

Be prepared to document where that cash came from - in your case, that's easy, your HELOC.Would be happy to help you with that sort of transaction if you want to reach out - I find a lot loan officers are unfamiliar that this option even exists. 

I would hate to lose the lower rate loan and not be thrilled to give up the prop 13 savings.

Using online sources to do an LLC seems a bit silly.

To find a triplex or bigger property, look at loans that count your rental income, like portfolio loans and DSCR loans.