Custom Appointment Booking Website

I’m starting from scratch and need a complete website where visitors can browse my services, pick a time slot, and confirm their appointment in one smooth flow. The core of the build is a dynamic booking engine that lets users sign up or log in, view real-time availability on an integrated calendar, choose a package or service combination, and pay securely on the spot.

Key elements I must see working together:
• Secure user-account system with simple registration and profile management
• Calendar integration that syncs availability in real time and supports adjustable time blocks and slot limits
• Payment gateway setup for immediate online checkout (credit/debit card and popular wallets)
• Flexible product/“package” builder so I can bundle services or offer add-ons during booking

The site should load quickly, look modern on desktop and mobile, and give me an easy admin area to update schedules, prices, and content. Feel free to recommend the best stack—whether WordPress with premium booking plugins, a custom React front end with Node, or another robust solution—as long as you can deliver a polished, fully tested platform ready for launch.

When you reply, please outline the tech you’d use, any prior booking sites you’ve built, and an estimated timeline from kickoff to go-live.