H-4 filing fees are in the $250 to $300 range, you can get exact information from USCIS website. The H visas are employer driven, self file options do not exist. A PhD in Organic chemistry can actually apply for his or her own green card under the national interest category (if field of study is innovative enough) but NOT an H-1. A University or a company has to do the H-1 filing for him. I am guessing the $2150 for H-4 you are mentioning involves a lawyer unless I am way off in my fee estimate. Frankly, you don’t need a lawyer for H-4, it is a very simple visa category. $400 should do it if the $85 biometric is also needed.
Dr. Sandeep Shankar
Academic Advisor (India) to The Executive Director
Colorado Heights University
Denver, CO 80223, USA