Here is a list of all the (credible) yoga teacher training programs in Bali, so you can compare the prices.
East+West : $3,950 All-Inclusive (shared room)
Website: https://yogaeastwest.com/yoga-teacher-training-bali/
Blooming Lotus Yoga: $4,136 All-Inclusive
Website: https://www.blooming-lotus-yoga.com/200hr-teacher-training/
Intuitive Flow Yoga School: $4,500 All-Inclusive
Website: https://www.intuitiveflow.com/
Power of Now Oasis: $3,100, No Accommodation or Food
Website: https://powerofnowoasis.com/
Santosha Yoga School: $2,300, No Accommodation or Food
Website: http://santoshayogainstitute.edu.au/yoga-teacher-training/level-1-ytt-200hr/
School Yoga Institute: $2,450, No Accommodation or Food
Website: https://schoolyogainstitute.com/200-hour-yoga-teacher-training/
Routes of Yoga: $3,900, All-Inclusive (no breakfast)
Website: http://www.routesofyoga.com/full-events/2015/8/6/200-hour-yoga-teacher-training-residential-bali
Yandara: $2,970 All-Inclusive (16 days)
Website: http://www.yandara.com/training-locations/bali/16-day
Zuna Yoga: $3,600-$4,200, All-Inclusive (shared room)
Website: https://www.zunayoga.com/200-hour-yoga-teacher-training.php
School of Sacred Arts: $3,650, No Accommodation or Food
Website: http://www.schoolofsacredarts.net/yoga-retreat-bali/
Sadhana Yoga School: $4,500, All-Inclusive (For a Triple Room)
Website: https://sadhanayoga.com/
Samasti Yoga: $3,490, All-Inclusive (2 meals a day)
Website: http://www.samasti-yoga.com/