Hi,
I'll be pleased to complete this project for you. Let me introduce myself: I'm a CCIE (R&S) certified network and systems specialist with 7+ years of experience in configuring, securing and maintaining complex networks for large enterprises.
I'm passionate about Ubiquiti Unifi and have extensive hands-on experience with setting up Unifi controllers (cloud based and as well as cloud key), USGs, edge routers, APs and switches. I am highly proficient in creating Wifi Captive Portals that integrate seamlessly with Unifi cloud key.
I've recently implemented several WiFi Captive Portal projects for high-profile customers like McDonalds, Sephora (cosmetics brand), hotels and several startups. I can share you their links, screenshots and videos as well. As proof of similar Freelancer projects that I've completed or are under progress please check out the following links:
https://www.freelancer.com/projects/php/Unifi-Custom-Portal-with-Email/
https://www.freelancer.com/projects/php/cpative-portal-ubiquity-unifi-access/
https://www.freelancer.com/projects/graphic-design/social-media-integration-wifi-captive/
https://www.freelancer.com/projects/graphic-design/create-customizable-Wifi-landing-page/
https://www.freelancer.com/projects/php/internet-hotspot-unifi-router/
The last project specially is a big project with around 30 McDonald's restaurants in Brazil. It's setup is very similar to yours. Do send me a message and we can discuss this further.