PHP: Website Postcode Checker & UI

Brief:
NEW: Postcode Checker

Site: www.mthnetworks.com
Current: https://www.mthnetworks.com/postcode-checker/

Example Openreach FTTP: NN15 5XX, Property number: 10
Example OFNL FTTP: NN18 8GN, Property number not required

The current system works, most of the time - but the UI is not very appealing and their are errors sometimes, it is also slow.

We need two forms;

1. Postcode only > Submit
2. Postcode, plus Contact Name, Email and Phone Number > Submit (Contact Details Optional)

With the above two forms, we will put them on our website in different places. The website is run using Wordpress, so this could be created as a Plugin.

When the user visits their website, and submits their postcode, we should do the following;

1. Make an API call to “Get Available Address”
a. This should return a list of available addresses and address references at the postcode given (ie, property numbers)
2. Display this list to the customer for them to select the correct property number or name
a. We should also add an option for “NONE”, where the system will continue with the postcode-only
3. Once the user has selected a property number (or NONE), we should first check the postcode against the OFNL database (local SQL database, db name, table, schema can be provided)
4. If the postcode is present in the OFNL Database, we would redirect the user to the OFNL Internet page
5. If the postcode is not present in the OFNL database, we should check the Openreach Database (local SQL database, db name, table, schema can be provided).
6. If the postcode is not in either of these databases’ will need to use the address references from the API in order to make a final API call to request available services at that address. If FTTP is contained in these available services, we should direct the user to the Openreach FTTP page. We should also add the postcode and property number to the Openreach FTTP database(local SQL database, db name, table, schema can be provided) for quicker repeat lookups
7. If the postcode/property is not found in any three locations, it should direct the user to the Contact Us page.
8. Finally, we should add the data from the search (Postcode, property number, contact details) to the results table (local SQL database, db name, table, schema can be provided).