To answer your question, ask yourself these questions...
Do I make money on a cash sale? Or do I make money on a loan purchase?
Is your money working for you or are you working for your money?
How much monies do I need to use to make this a win-win.
Yes, I'm answering a question by asking a question. But you must consider all ramifications of tying up your monies long term.
Which way do you create the most benefit is what you're really asking.
It is different for every situation. So there is not a right or wrong answer. It's what you are most comfortable with. Make yourself a pro and con list. How much risk can you absorb? Only then, will you know the answer to your question.
Hope that helps!