The only two I have used are I think it’s called B52 (owned by the same people) top end of BMV a bit rough and ready everything you need bike’s, Xtrainer, running machine and free weights at the time I was there it was September it was 10tl a day or 50tl a week the other one was not far from the dolphin- less roundabout very similar equipment to B52 but not as rough and ready the young girl who worked there was very pleasant but didn’t speak English if I remember it was 15tl a day and I think 80tl a week.
B52 had a sauna but it was never on you didn’t need it some mornings it was reaching 38 degrees before 11am ( no air conditioning just open windows)
The other one had a sauna, small swimming pool and air con
Hope this helps