Does anyone charge more for dogs who pull heavily?

My standard rate is $15 and puppy rate is $20 for 30min walks. I've been walking an 11-month old dog, who recently turned a year old and therefore not automatically categorized as a puppy. However, this dog pulls really hard, has no impulse control and lunges at people. I therefore think that I should charge a higher rate. Does anyone do this? How do you approach this price with the client? I've offered to work more with her on leash walking, so the owner is very aware of the issue. Should I just state the extra fee on my profile? And I do mean that this would be for dogs who pull non-stop, not for the occasional pullers.