Structure for Investor Notes paying 21%

I’m new to this forum and just moved to Florida from Connecticut. Love the weather and the local real estate economy. While I have substantial experience in business and real estate, I want to raise money from investors to allow me to continually fund rehab properties. I looked into conventional and hard money, all have limitations and even with hard money, with points and fees I’m in the 18% area. I need advice to structure notes for individual investors that are secured by property-paying 10%, but that also have an equity kicker at resale so the effective yield would be in the 21% range. I have a C corp, and my attorney is suggesting the properties go into a LLC partnership with the corp so that the investor has a note from the corp as well as a mortgage. I am just learning the LLC and land trust areas, so I was hoping there might be an experienced person who could provide some insight on the best way to structure for yield, protection and taxes, as I would like to evenually be working from a larger warehouse line as I get more established. BTW-the properties are residential with typical ratios of 50-65% of ARV. Ary ideas would be appreciated.