What does this have to do with leverage? A lot. Films are built on leveraging relationships. The "I'll scratch your back, if you'll scratch mine" mentality runs this town. So when Christian and Desmond agreed to be part of Not Since You, I was agreeing to support them the rest of their careers as well. I got two wonderful actors in our film, but they also got two great roles, lifelong fans and support for the future -- and hopefully more work -- from my company.
Leverage is very similar to bartering. You may have something of value that another vendor or piece of talent would like to have. Maybe a vendor or an actor is looking to get producing credits in order to increase their visibility. In turn, you need your post production handled or an actor to work on a deferred basis because you are out of cash. Both sides are then using what they have of value in order to leverage the ideal outcome for each. You can offer a producing credit and they can offer their services. It's a win-win leverage.
Some leverages can also feel more negative than positive. The one who gains the most in a leverage is usually the side that doesn't "need" the outcome as badly. For example, if you need a certain actor more than the actor needs your film, you may find yourself being leveraged to give more money or perks because you need that actor very badly in order to trigger the financing, etc. These instances of leverage can sting a bit but in the end, you are gaining the thing that is getting your film made. It's just a higher cost leverage than you had hoped.
Leverage is a very useful tool. You may win large by strongly leveraging your value on one deal but then find you are being leveraged heavily in a way you don't like on another deal. The good and the bad are a package deal when it comes to leverage. Hopefully, you will come to respect the power of leveraging and use it to your greatest advantage and success.