How much is the monthly fee for Manta?

Could you please elaborate on the monthly fee structure for Manta? I'm interested in understanding the cost associated with using this service. Is there a flat fee, or does it vary based on usage? Are there any additional charges or hidden fees that I should be aware of? Clarifying the cost structure upfront will help me make an informed decision about whether Manta is a suitable option for my needs. Thank you for your assistance in providing this information.