Hi,
Plan to complete:-
We have done such type of projects in Oracle Apex. We can use handler and use get/post/delete method to consume web services. We can demo our work. As suggested by you we can plan for mile stone per module.
About Us:-
We have been working in Oracle Apex(12+ years) in Oracle Apex Development 19.1, 18, 5.1,5.0,4.2,4.1,3.2,3.1, Webservices, Oracle, Plsql, Jquery, javascript project from last 14+ years.
Our History:- We have made different application like Hospital, School, fleet, Airline booking by Agent, Energy consumption (using Traffic control and google maps), Saloon booking, Basketball. We have reputed customers from USA, Mexico, Uk and India.
Demo on request:-
We can show you Demo, if interested on skpeid:- amen5699.
Regards,
Amen