Coaching for ADHD-diagnosed Teen

Hello. 

My high school sophomore daughter was diagnosed with ADHD in December. She also has anxiety. I am navigating the help and support systems she will need to succeed at school and learn skills for the future. She had excellent grades until last year, but this semester's grades tanked when she had a big courseload and AP classes. She did not submit homework, could not study, lacked focus, and did poorly on tests. In addition, I see that her organizational skills are highly challenging - her room, closet, and table are in disarray, and so are her study materials.  It is very stressful for her to live like that and for us.  It seems we are always on the edge because we don't know what will happen next - e.g., she forgot a birthday and needs to go buy a last-minute gift; or she left homework at home and needs someone to drop off, and so on. I am assuming many other parents of teenagers, especially those diagnosed at later age and, as a result, haven't gone through long-term coaching/training, are probably in the same boat. Is that correct?  

So, I feel she needs help from a therapist to address the anxiety; but she also needs some "life coaching" type advice to gather her life; and also needs coaching/tutoring focussed on making sure her schoolwork is managed properly; and lastly, she needs some subject-specific tutoring in certain topics as needed.  I don't know about other teens, but, she is not interested in listening to my advice or does not want me to be her accountability partner. For professional help for all of these, I can imagine that the costs of getting all these services can quickly add up. In BPN, I have read about organizations for executive functioning/study skills for ADHD; their rates are about $80-ish per hour. I looked up another academic coach whose rates are $185/hour. I heard recommendations that the EF skills coaching should be continued for a year for the kids to "learn" the skills; and @ twice a week.  These can add up to the cost, because EF/study skills are only one fraction of the skills the kiddos need to learn - there will be the cost of therapists and subject tutors.

I am not clear about what type of services these organizations will be providing.  Especially the executive functioning skills for teenagers: is that a glorified form of maintaining planners (or any other system that works with the particular child) and being accountability partners to make sure they complete tasks? Or is it indeed something more than that that justifies such fees? I read parents saying they got excellent results but I don't know if those tutors were teaching subject matters also or just EF skills and what was the result, specifically. I was looking at some online tutoring platforms, and many tutors offer "executive functioning skills for neurodivergent kids" at a  fraction of the cost. I am aware that there is no quality control on those services. 

So, those who have experience supporting ADHD teens - what is your strategy? How have you managed through these high school years, when academics are important, but so are life skills and parents' sanity and funds are limited? Any advice/thoughts? What am I missing here?    Another question: does anyone have a recommendation for a life coach who advises beyond study /EF skills? Or perhaps workshops/support groups for teens?  Thank you.