Sell your place and build
This option puts what is left from the sale, after the mortgage and selling costs, towards your new build.
Keep your place and build
This keeps your current home in the numbers. It includes possible rent, the cost of owning it, and the extra lending you may need to carry both properties.
Wait and build later
This moves your home value, section and build costs, income, and savings forward. It shows a possible what-if, not a forecast of where the market will go.