The five critical facts about loans and mortgages include: 1) Construction loans are for new builds or major renovations, while mortgages purchase existing homes. 2) Construction loans are short-term, unlike long-term mortgages. 3) Interest rates are higher for construction loans. 4) Mortgages often offer fixed, lower rates. 5) Construction loans provide flexibility but require careful budgeting. Understanding these can guide your financial choices effectively.