Three figures appear on almost every other RBT practice page, and none of them appears here.
The passing score. BACB sets it with a modified Angoff process — a panel of certified subject-matter experts, approved by the board — and does not publish the result. A new score was established for the 3rd-edition outline. Every percentage circulating on the open web is folklore.
The pass rate. What BACB actually publishes is first-time pass rates broken down by 40-hour training provider, once a year, and the spread between providers is very large. There is no published overall figure, and the third-party aggregates that claim one disagree with each other.
The cost. There is a BACB application fee and a separate Pearson VUE appointment fee, plus whatever your 40-hour training charged. The current table is in the RBT Handbook on bacb.com, and it is republished quarterly.