New build on lot with older homer

Hi wanted to see if someone could give me some insight. I am looking to build a new home. I am in discussion to buy a lot with an older home currently there.  I plan of tearing the home down and building a new home in its place. Would anyone have advice as to how to go about this. My goal is to use the least amount of down payment as needed. I have looked into construction loan to permanent. Most require 20%. I wanted to know if they're other options.