Mortgage AND Private Lender

[Corey Elfman]

I'm 17 days from closing on my first deal. I locked in a 30-year fixed at 6.5% with a local credit union (included points). A family member has since asked if I'd be interested in financing $100k of the deal with them at 3%. Is the best path to close with the 30-year fixed as is and immediately pay down $100k? Or tell the mortgage company that I'd like to put down a larger percent at closing? Other options?