Customize an existing Flutter App script - Long term Flutter and Laravel

I have purchased an INSTA script from codecanyon in Flutter and Laravel backend. I need someone to do customizations on the APP.

For the script, please check: shorturl.at/ehnU2

Customizations needed:

- Option for submitting KYC Document (2 files)
- Video Filter addition (Image filter is already there)
- Video Timer set
- Login with OTP and SMS (Feature already done)
- Changes in Design based on Logo and colors
- Option for admin to approve/disapprove a Video

Budget: Upto 10,000/INR
No advance payments will be provided. The work would be divided into 2 phases , and the developer will be paid on end of each milestones

The developer needs to sign a contract/NDA to start working.