Process for pre-selling event tickets and scanning the tickets at event entrance

[anitasdra]

The SDRA is a drag racing facility in Saskatchewan, Canada. We use square terminals at our event gates.

It has been suggested that we set up an online pre-purchase of tickets for our major events.
I am wondering what all to do to set the event up in our online store, and have each purchase generate a barcode receipt that can be scanned at our event gates.

Has anyone done this before?
Did you set the event up directly in square, or use a compatible app?
Was it a challenge to reconcile ticket purchases?
What scanner did you use at the event gate?
Is there a report that can be done at the end of the event to show number of tickets scanned? Does the scanner recognize if someone tries to reuse the scanned code?
Did you rent the scanner or purchase outright?
What challenges did you have?

I know it's a lot of questions at once. Thanks for reading.

Anita