Take a tour of the facility, and see if there are any barriers that will make it harder or impossible for you to exercise. If you see problems, tell the person who is taking you around and see if they have solutions already.
If the cost to join is too high for you, ask whether the center offers scholarships, sliding fee scales based on income, bartering systems (membership for assistance with a class) or other assistance programs. (You will be more likely to find such policies at YMCA's or other public community fitness centers, such as park and recreation programs.)
Ask whether the facility will let you bring a companion to assist you at no additional cost.
Ask for a guest pass for a small daily fee or no cost, so you can try-out the facility for a few days.
The center should not require anything special from you because of your disability that they do not require of every member. For example, they cannot make you get a doctor's permission to be there.
