The SBA 504 loan is the best choice for buying commercial property. Money can be used to buy a building, finance ground-up construction, or rehab an existing building. With the SBA 504 loan, you are likely to have the lowest interest rates and a 25-year repayment term. Borrowing limits are normally $2 million for commercial property. Key requirements of this loan include the owner must occupy 51% of an existing building or 60% of a new construction building.