As it was a large step with the cost and not really knowing what to expect, we did a little research as you are doing. The school offered a trial day which enabled our son to attend what would be his class for a full day of education. He followed their schedule and was brought in just as if he was attending already. After only this one day, he was adamant that he wanted to return as soon as possible. Because of the limited class size we had to wait until the beginning of the next year for a spot to open up. This was at least the light at the end of the tunnel for us. Payments where done on an installment basis which we were able to budget around. The time to find a spot assisted us with this planning. We were also invited to a seminar about the disabilities tax credit and RDSP program that we may qualify for. I found these very helpful and informative.
The responsiveness from the admin is excellent. When we found that my daughter was doing poorly in her previous school, we were given a tour. We took the opportunity to do a one day trial. It was a good fit. The admissions process was seamless. All information is sent and is very clear. After I signed consent, they connected with her previous school to obtain her Ontario Student Record. Everything is laid out pretty clearly from everything to the Enrollment form to the payment schedule. My older son who remained at his school during high school, did 2 summers of summer school in advanced mathematics courses. I say this because it is important to know that your child can attend summer school (very small class size of 4-6 students) all the while attending another school during the school year. It raised his marks. Admissions for summer school are even easier. All forms are on their website.
The application process was simple and welcoming. It was not stressful at all. We were never made to feel like our child might not be "accepted". The trial day is a very effective way of letting students and parents find out if the school is right for them. What stands out to me about that day, apart from how happy and welcoming the staff and students were, was my child's reaction at the end of the day. He emerged from the school with a giant smile and said, "THIS school is where I belong". Based on his reaction, we knew that our long search for an appropriate school to address his/her needs was finally over. Most aspects of the school (staff, processes, etc.) are flexible in accommodating parents and students with special circumstances (e.g. joining half way through the year, etc.).