Professional association seeks room booking software including billing system

We are a professional organization and are looking for room booking software, including a billing system, for a facility that will organize exhibitions and events in the future.

The software should meet the following requirements:

• Suitable for events and exhibitions
• Record and manage room bookings according to dependencies (room -> seating -> people)
• Take various exclusion criteria and dependencies into account
• Double bookings are possible in individual cases (e.g., reception in a room with a simultaneous art exhibition); this must be displayed accordingly
• Booking requests via a contact form on the homepage
• Internal bookings via administration
• Calendar display of occupancy on the homepage and internally
• Internal view records all dates, public view only those that have been approved for publication
• Billing of events and catering according to internal pricing system
• Web-based solution desired

2-5 software workstations are planned.