Web based member's area + payment system for app

General information for the website: Web based member's area + payment system for app
Description of requirements/features: We have an app developed and a site to go along with it, but are in need of a comprehensive user login area on the site.


Brief:
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We have a relatively simple app that helps our client solve the following issue: "Once a contractor agrees with his client to put in a yellow floor in their house, but half way down the job, the client changes his mind and wants the floor to be green. In order to process such changes, several forms need to be filled out."
What we are looking for is a web developer who can provide us with a member’s area on our site that syncs with the app.

The app will be free for download in the iTunes and Play stores and have certain free features. To unlock the premium features the user will have register on the site’s member’s area (or through the app, by being directed to the site). Paying for the premium subscription can be done monthly or annual.
In the member’s area the user can create new forms and export them as PDF files (there will also be a list of approximately 125 of standardised forms already available for users), but also upload Excel and Word files which then are automatically transformed into forms. The forms can be managed in this member’s area (created, signed, edited, deleted, downloaded as PDF and shared through email). Two examples of forms are attached.
Voice recordings, videos and photos can be managed here as well; created in this member’s area, deleted, downloaded and emailed.

Every user will have their own profile with the following info:
o Company name
o Company logo – you an set best requirements for this (we were
thinking *,jpg and *.png support)
o Address
o Phone number
o Email address
o VAT Number
o Web site URL
o Name contact person
o Dropbox account link (to save voice recordings, forms and PDF’s)


Other required features:
- Retrieve login details
- The payment system
- There will be the need for two roles in the member’s area:
o Regular (the role every user will get)
o Super admin (the role for the owner of the app and developers that allows them to edit the member’s area, but no access to forms and/or privacy sensitive information)

All changes made in this member’s area must sync directly with the app.

The whole member’s area will need to run from our own site, no external links and I need to obtain all files in order to successfully finish the project.


What I need from you:
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I need the web developer to create the member’s area, including the payment system, set it up on our site and ensure it syncs flawless and directly with the app. Also, I will require frequent updates on the progress.


What I need to know from you:
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Show me examples of previous work
Tell me how long will it take you?
What will the cost be (fixed price strongly preferred)?


I am in search of a fast and reliable freelancer (or company) which preferably is based in Europe or the US.



Happy bidding!
Extra notes: