Well, I see that you offer some revisions, when you offer revisions you have to provide the ones you offer with the gig, but once the buyer has used up the ones included with the gig, just tell them you’d be happy to keep working at an additional cost.
I have to say I don’t offer any revisions at all but if a buyer wants to make a change I usually base it off how much work needs to be done and the attitude of the buyer, if a buyer has had great communication, is understanding, and overall a great person to work with, and the additional work is nothing but a minor change, then I usually don’t mind making this small change.
On the other hand, I’ve had the unfortunate event of having a buyer with poor communication and not too great to work with, not to mention asking for a complete rework of the project because of their own lack of communication, well to this person I didn’t hesitate to let them know “I’d be very happy to continue working on the project at the additonal cost of $x”.
Just, whatever you do, make sure to stay positive and professional. Remember, just because you’re a freelancer doesn’t mean you’re some random from the interwebs, you’re a BUSINESS, therefore buyers should treat it as such and so should you. Don’t be afraid to set boundaries! Good luck! :))