Is it possible to add racers (if needed) before going to the payment page?

https://www.jotform.com//?formID=61865164371156

In general I would like a family to fill our the form for their whole family (with individual participants) and only have to check out 1 time.  

To my understanding I think what you mean is that you'd like to be able to add one or more racers such as in a whole family of racers and have them listed to then send to your paypal payment page.

The best way to do this would be to use something like our configurable list widget which you could allow one or even several racers to register before submitting your form to pay.

I think so.  I won't lie the widget is a bit much.  I'm not real clear on the use of it.

We have a guide here https://www.jotform.com/help/282-How-to-Set-Up-the-Configurable-List-Widget that shows you how to set it all up. The only thing you would need to do is choose which fields you want to use to collect the racer name and information.

If you still don't like that though then another option would be to use several name fields and a radio field then use conditional logic to hide those as a workaround but doing it this way is more tedious.