Hairstylists can't color your hair and do highlights at the same time. After they color your hair and you still want highlights, they can highlight your hair a few days later. But it's not necessary to put highlights in your hair if you're going to get it colored blonde. The cost depends on which beauty salon you go to. You can call up the salon and ask them to give you the price for a monthly touch up. Now that I've answered all your questions and you will be getting your hair done professionally. This thread will now be locked.