What about the price for a group of tickets – can we sell those at whatever price we want?

You may sell groups of tickets as along as each individual ticket price does not exceed the $2 limit. For example, you may sell a group of 10 tickets for $20 ($20/10 = $2) or 10 tickets for $5 ($5/10 = $0.50) but you cannot sell 10 tickets for $25 ($25/10 = $2.50).