You might find it convenient to get your finance sorted through the car dealer. But there are a few eye openers that might interest you:
A secured loan is one which involves you supporting your loan application with a valuable asset. The provider can take possession of said asset upon payment default. An unsecured loan does not involve the support of any assets and usually involve higher interest rates.
A balloon payment is a lump sum amount that is paid towards the end of your loan term. The payment of such an amount could result in lesser payments during the term.
It is important to find out such information from an expert who deals with various lenders. This will help you and your advisor to select the suitable product and provider based on your requirements.