Build a PHP Webapp with Zoho Subscription and Xero Integration -- 2

I need someone with experience working with the Zoho Subscription API and Xero in a PHP Web application User Sign Up Process: For someone to sign up for the subscription service, they fill out a Zoho hosted form on the website and are then taken to a page on the website to complete their profile. I need some of the Zoho information they filled out on the initial form to be passed to the website database so when they add a username and password, it’s all tied to one account. The userID in the website database would be the one it gets from Zoho. That way the our admins can reference between both the website and zoho subscriptions. I am not looking to mirror everything between the two systems - just share available products, basic account information, subscription and payment status and handle changes to the account. Once they are a member of the website, I need to be able to update either system and have it update the other. From Zoho subscription to the website: Every time they log in, it should check who the customer is and update the website database with the following: 1. Billing status 2. Current Plan 3. Last Billing Date From The Website to Zoho: I would need to update Zoho anytime I do the following in the website: Everything on the website should work off two pages but you can create separate pages for each Zoho hosted page if needed. One page allows the user to edit their profile information, the other does their subscription change or cancel. 1. Change subscription (so Zoho can process the upgrade and bill them) 2. Cancel account (so Zoho can stop billing them) 3. Change user details (username etc) Zoho subscription Hosted Pages Zoho Offers hosted pages option for signing up, upgrading, updating credit cards etc. To keep things simple, I would like to leverage these. Xero Integration Zoho subscription provides integration to Xero through Zapier. This is an extra requirement for invoicing. When a user subscribes to a plan it should trigger Xero to automatically generate an Invoice; and the Invoice imported into Zoho subscriptions instead of using the default Zoho subscription invoice. Please communicate whether you have experience specifically with Zoho Subscriptions and Zapier.