Need a freelancer for Ruby on Rails - ActiveAdmin / ActiveMerchant

We have a Ruby on Rails environment set up on Heroku that uses ActiveMerchant and ActiveAdmin. The freelancer will not have full access to our codebase. We would like to set up screenshares where the freelancer will help guide us with the necessary changes. We can share specific files with the freelancer, but the entire codebase will not be shared. The current system requires registration and login to purchase an item.

We are looking to modify the code to allow guest purchases that do not require registration and logins.

Requirements
- must be highly skilled with Ruby on Rails
- must be highly skilled with ActiveAdmin, ActiveMerchant, ActiveRecord, SimpleForm
- must be comfortable in English(I speak Hebrew and can communicate fluently in Hebrew) and can communicate through screenshares.
- must be comfortable working with PostgresSQL
- must be comfortable working with Heroku

This project will be paid hourly based on the number of hours worked. Please bid with your hourly rate.