I would highly suggest using Knack.com. It easily embeds into your Webflow site as a web app.
I recently found it, and it’s been awesome. I’ve been able to create a scoring application for a company that hosts marathon events. The app needed to have meters logged, display meters logged, show leaders, allow sign-up into teams, show account progress to 100,000 meters, and a bunch more (we’re still working on it for the November 24th launch, but we’ve already got users signed up).
Knack is robust enough for something like that, and simple enough to create your own booking calendar with Stripe/Paypal integration.
Check out this events calendar template: https://www.knack.com/templates/event-calendar/demo/calendar
This calendar template can be embedded right into your website. Events can be filtered, categorized, and color-coded. The community submits their own events for approval.
And you can find other templates here: https://www.knack.com/templates
Plus Knack integrates with Zapier if you need to import some of that info into your Webflow site: https://www.knack.com/tour
You can use my referral link to sign-up for free: https://www.knack.com/r/knack-webflow
Their cheapest plan is $39 more than squareup.com with more flexibility.
Hopefully this helps