The short answer
Confirm that the land can support the project before you make a final commitment to a home.
You can compare both at the same time
It is fine to shop for land and floor plans together, but verify zoning, restrictions, utilities, septic, delivery access, financing, and site costs before closing on land or ordering the home.
Match a candidate home to a candidate parcel
Take the floor-plan dimensions and proposed installation information to the professionals reviewing the land. They need more than a bedroom count to consider placement, access, setbacks, and utility locations.
Before spending money you cannot recover, ask what happens if the parcel does not qualify or the selected home will not fit. Have any purchase conditions explained by the professionals handling the transaction. You can narrow the home search while the land is being checked without treating either choice as final.
Use a simple side-by-side comparison
Keep one note for each parcel with the asking price, known site work, unanswered questions, and the home you are considering. A cheaper lot may need work that another property already has. Do not count an unanswered utility or access question as a zero-dollar item. The land checklist below helps you keep the same questions in front of each person reviewing the property.