Build a house on partner owned land

[Mike Hancock]

I’m looking to build a small house for a potential rental on a plot next to my partners rental who has the mortgage and land in their name. I have a private investor to fund the build but needs to be in my name to pass to him for insurance to build. What is the best way to get the plot into my name from my partner in order to have my builder start construction. It’s completely complicated but any advice would be appreciated.