Software Development for a small retail business

Require a solid software developed for a new retail business:
Requirements Software:
- Multi-user application
- No authorization levels (all users have access to the full application)
- SQL Database
Main functionality:
- Select item (not from ecommerce website), Calculate quantity, Customer Order, Purchase Order / Receipt, Order fulfilment (installation work done/fulfilled at client's)
- important to have Integration of https://wizart.ai/ software as a menu selection of this software
Expected Performance of this software:
- Wallpaper selection by customer via Wizart.com (as a side view)
- Calculate wallpaper rolls needed
- Create quotation/order for wallpaper bought by customer (for customer copy)
- Customer pays wallpaper bought (manual input)
- Create purchase Order of wallpaper based on sales order to the supplier (without revealing customer data)
- Register goods receipt once wallpaper is received from supplier (manual indication)
- Schedule job in the software for wallpaper installation basically, schedule staff for installation
- Create Master Data for supplier and wallpaper