If you have extra charges that are related to but not part of room charges, you can set them up via the Add-ons items. The latter are available to add for each reservation.
In the Admin Settings, click on the blue link Add-Ons:
Click on the blue button Add an Add-on:
Fill in all information: place the name (Charge Title), the price and the applicable tax/es, and select whether the charge is to be applied on a nightly or a reservation basis. For reporting purposes, select the right Revenue Label from the scroll down menu and click on the blue button Save when done:
You will be given the option to add any of the newly created Add-Ons directly in any reservation folio:
If you click on the link, another window will appear; use the scroll down menu to select the right charge among the ones you have created: