You can charge a booking fee if you want to. However, if you decide to charge the customer a service charge or booking fee, these charges must be made in accordance with all applicable laws, rules, and regulations.
If you choose to do this, your travel agency will be responsible for and liable for the charge made and for the collection and repayment of the charge made. You will also be responsible for any customer complaints that arise on the matter, and responsible for the remittance of applicable taxes. Your travel agency must also unambiguously notify and inform the customer that the charge you are adding is made by, and solely for the benefit of, your travel agency.