If there was an 80/10/10 offered on a $1,000,000 purchase in FL that did not require that the seller hold the second, Cross Collateralization of other property or asset (i.e. CD, Mutual Fund, Stocks) that info would spread throughout the mortgage industry like Wildfire!
I know of a bank that will do a 100% (90/10) but only in central FL and for medium income borrowers.
Contact me if you'd like additional information;
Luxury Partners Realty
16950 Jog Road
Delray Beach, FL 33446
I hope this helps and let me know if I can help you.