You may have addressed this one already, but I was unable to find any postings related to it. We offer tours twice a day, with a limit of 20 people. However, we offer two different prices for Adults and student tickets. So one user would make one reservation for 3 adults and 2 students, for a total price of 3 tickets @ 10 + 2 tickets @ 6 = 42.
Most of the systems I have looked at allow for multiple ticket purchases, but not at different prices, or they don't work against an event maximum. We do not need / want each person to register, we only need the info for the person who is purchasing and the number of each ticket type. Also, we don't need to have tickets printed, just the reservations made and the tickets payed for.
You can set fee values on those custom fields so based on how many tickets are selected, the price is calculated accordingly. No problem. Only thing is that will not work towards your event capacity check.
To incorporate the capacity, you'll need to offer both individual and group registration options. Create one custom field in this case:
Ticket Type: Adult / Student
This field would be used for an individual, or also for each member of a group registration so each ticket is priced correctly... and the number of tickets is counted against your event capacity. In a group registration, it will go member 1, member 2, etc and you could set those pages to show whatever fields you want. It could just be Name and Ticket Type. Technically, it could just be Ticket Type only if you wanted for each member. Up to you of course.
Either way, you can definitely accomplish your task.