M.B.
First of all I want you to know that I understand where you're at, you want the best for your child and finding the best is a sometimes lonely and daunting process. You are a loving parent and thats a great start.
My child is on the spectrum (SPD). All of his therapists have always used the DIR Floortime model which seems to be the preferred route unless your child is on the more severe end of the spectrum, has aggression, has problems following directions etc. If your child has classic autism Ive heard the ABA model is the best because it is highly structured and therapist lead. If not, I would suggest DIR which is more child lead and encourages learning and their own decision making process. Ive heard that ABA is not as beneficial to those that are higher functioning because it creates robotic like responses (because thats whats needed to get through to the more severe). But you don't want that in a high functioning child. Not knowing your childs issues or age its hard to say.
When I didn't know a lot about the different methods well meaning outsiders and ABA offices would suggest ABA because they either didn't know his specifics or wanted the money.
Have you had a diagnostic from a qualified team? They would be the ones to tell you which therapy model would be best for him from an unbiased point of view. If you need help finding a diagnostic in your area I can be very helpful, please send me a personal note.
If you've already been told to get ABA you ALWAYS want to interview a perspective therapist for group or individual therapy and sit in on all the therapy sessions until you are comfortable with their process and that they understand your child and his specific pressure points, also how he communicates. Ive walked out of many places who told me that they don't allow the parent in the room and found ones that wanted to me to learn and feel comfortable. They will sometimes tell you its a violation of HIPPA if its a group class which is total bs, they can still let you observe for 10 minutes.
I always ask if even once Im comfortable that if he is upset or asks for me that they bring him out to me in the waiting room. If they tell you its better to let them cry it out, well thats your call...I personally don't believe in that.
It is totally the therapists preference. Everything should be transparent with your child.
There are a lot of websites that explain ABA but of course every therapist is different.
Best of luck to you