For me what "No over-hours" on a front page means is that you're the lazy kind. It means that not working is more important to you than doing things right.
Again, I'm not going to expect a contractor to work over-hours, at least not without paying. And I understand separating work from personal life. I'm the first one asking for that. It's very important that anyone who work have a great life balance. It makes better people, better work quality, better work environment.
What are you trying to achieve by putting this on your front-page ? Or actually, putting it anywhere on your website ?
Preventing client from getting advantage of you ? Then maybe the way to go is to say no when the problem arise. Contracts should protect you...
If you're not doing over hours it's fine, but discuss it when you come to the details. You actually probably know how to approach a customer more than me as you seem to have way more experience.
It's like when you started dating your wife (I presume you have a wife since you seen to have a kid). First time you saw her, did you say "Ok we're going to date, but 'NO <put something here you that don't like in other people>'. She wouldn't want to hear it.
What do you think ?