If you are already a freelancer and have been for a while you'll know of how much time is wasted just waiting around. Waiting for a call from a client, waiting for an email, waiting for feedback, waiting for payment...the list goes on. Thankfully there are clients who are quick when it comes to everything. But for those who keep you waiting, put a penalty on them.
All that time you waste waiting around could have gone towards another project, whether it be for a client or a project of your own. You could have used that time a lot better.
I got frustrated with some of my clients taking their time to respond to me. So instead of me waiting around for nothing, I started getting paid for waiting around. When writing up contracts for some of my clients I included a penalty if they took 5 or more days to respond to any emails, calls or texts. Of course waiting 2 or 3 days is fine, we're all busy people, but most people can at least find 2 or 3 minutes to respond to an email in a space of 5 days.
My penalty wasn't something ridiculous, it was 50% of my hourly rate, a day. So if my rate was £40 an hour, I would charge £20 a day after 5 days without a response. So if a client was 7 days late, I would get £40. When the days go by it can add up.
My aim here wasn't to milk my clients of their money, but to speed things up, and it did, massively. It's amazing how much more responsive people are when you put a penalty on them.
When sending over the contract, do make the penalty very clear. Or it can be a very unwelcome surprise when it's too late.