Is it possible to have a limit on selections?

Also, we have a list of open seats next to each event and would ideally like to have the number of those seats auto-update as people sign up so it reflects for a user how many seats are left. Is that possible using jotform?

We have some widgets that will allow you to do this, you may set up an available quantity and it will decrease accordingly as your users are selecting the options. 

Here are the widgets: 

https://widgets.jotform.com/widget/gift_registry

https://widgets.jotform.com/widget/quantity_gift_registry

https://widgets.jotform.com/widget/inventory 

This guide will help you adding the widgets to your form: https://www.jotform.com/help/252-How-to-Add-a-Widget-to-Your-Form 

I hope this helps.