The cost of using LANREG is 20 cents USD plus 1% (compare to Eventbrite's 99 cents USD plus 2.5%) of all seats/tickets SOLD for an event, with a maximum of $1 USD per seat/ticket.
If the seats/tickets for your event are free, or you just want to make an informational posting, there is no cost to you.
LANREG will bill the event organizer once the event's start date is passed. This enables the money for ticket sales to go directly to the organizers, and reduces fees.
PayPal processing fees do occur with each transaction on top of the LANREG fee.