A derm is a good idea if you can afford it - many of the treatments that cost the earth when we were kids are now generic. Be sure to ask the doctor to try treatments that are available in generic first.
If she uses ANY acne treatment, including just washing her face several times a day, she MUST use a moisturizer. Dry skin develops teeny cracks in it and acne causing bacteria enter through these cracks. Even if her face feels oily to her she needs a moisturizer. Chances are that if it feels oily she will use products to dry it out. Right after she washes it, her skin will feel dry and tight. This will actually cause her body to create even more oil than usual because oil is how the body keeps it from developing those cracks. It is a major reason that she MUST wear moisturizer. Another is because the skin is the body's first line of defense against any bacteria or other problems, and is the body's largest organ.
If she uses a washcloth she MUST have a clean one to use EVERY SINGLE TIME she washes her face - in the shower her face must be the first thing she washes with the cloth, then any body areas with acne.
Phisoderm makes a great body wash for people with acne. You may need to find it online - I can only find it at WM occasionally.
ProActive helps some people, but it should be introduced in steps. First use the face wash for a couple of weeks. When your skin is used to it, then add the toner/astringent/step 2 stuff (not sure what they call it and too lazy to go hunt up the name from the other bathroom - gma buys it for Jessamess). Give that a few weeks before you add the lotion. in my opinion it is not likely to help you daughter. It helps Jess a little bit, but not a lot.
We use a topical product that really speeds the healing of acne after it appears. It is NOT sold for acne treatment. BurnJel Plus is about $5-$6 at Walmart and is available in the first aid section of the pharmacy area. It is a gel that contains lidocaine and tea tree oil - does not cause more breakouts, helps with any pain associated (acne can be quite painful - at least it was for me, and is for Jessie and Wiz), and speeds healing of any zit from about 6-7 days to 3 or fewer days. She doesn't use it as a moisturizer most of the time, just puts a dab on anything that is bothering her. It works whether she pops the zit or not (she has a hard time not messing with them when they are very painful).
It isn't a treatment to prevent them, but it does make living with them less difficult.
If your daughter wears makeup, ELF sells a concealer pencil/brush combo for $3 that has tea tree oil and salicylic acid in it and treats while it covers (
http://www.eyeslipsface.com/studio/face/concealer/concealer_pencil_&_brush). They also have a 30% off code for the line this is in (studio line) if you buy $20 worth before discount. Their items are good quality and make great gifts - esp their big kabuki brush for $8.
Regardless of whether she wears makeup or not, she MUST MUST MUST wear sunscreen every day if she uses any acne treatment, including oral medications. Most make your skin sunburn quite badly - even friends who had very dark or dark African American skin burned badly, often for the very first time. If she goes to play a sport after school, or has outside gym after lunch she needs to wash her face and put sunscreen on about 30 minutes before (or as close to that as possible).
Using moisturizer with sunscreen in the morning will not give her coverage all day, not by a long shot.
I am sorry this is a problem for her. I know how miserable it is.