It is the
PIO who would inform about the number of photocopy charges to be deposited separately after your application. If you are sure about the number of pages, than based upon the
RTI template we have provided at rtiindia.info, you can deposit the fees for expediting the process.
Also remember that the time from which the
PIO ask for the deposition of photocopy charges, that time is excluded from the 30 days cut off period.