Dear sir,
I've read your requirements carefully.
As an expert in Shopify app building, I could be a good fit.
Please check the recent Shopify (app) projects I've done.
https://www.freelancer.com/projects/php/need-Shopify-app-which-can/
https://www.freelancer.com/projects/Website-Design/Modify-Shopify-Theme-10618263/
I can start today and complete it within this weekend.
Kind regards,
Francis T.