Point of Sale, AR, and Inventory Management app with Postgres/MySQL back-end needed

I have a client that will be needing a new POS (point of sale) application to to be used at multiple terminals at once for their business (can be standalone on each install but must require authentication of username/password). The functionality must include: POS - Point of Sale Inventory Management Simple Accounts Recievable/Payabale Returns and RMA process Inventory tracking Printing (invoices, receipts, returns, etc.) Application to customer invoice in the form of credits (payments made) Customer and Sales Analysis (accessed remotely by sales staff and/or by owner/operator) Standard AR/AP/GL based reporting to show month-end figures. PDF generation and saving of month-end accounting reports to database Simple ability to search for several attributes and print results from search (e.g. by zip code, customer name, invoice number, customer number, sales territory - which could be combination of multiple zip codes, etc.) Web-based remote access for sales and management (using secure authentication) to view different levels of information (salesman only sees his figures, sales manager sees all in that territory, owner sees all sales across all territory and company, etc.) On Inventory management, include ability to add descriptive details on existing/new inventory, along with picture and standard inventory related data fields. Internally email (or fax-as-email) to customers as needed for invoices, receipts, or follow-ups, directly from the customer-side of the system. Accounting side should be able to show description and details of each transaction (if payment, via what method cash, check, credit and reference number (e,g. check number used) Mark sales as "defective replacement" on the customer invoice, relating to RMA as well Inventory alerts (via e-mail and/or report) to show when inventory is low for specific items, etc. Threshold set at the inventory item level Creation of dashboard-level simple sales figures for owner/operator to access remotely. POS is done at individual local-station terminals. Sales is done via local sales manager or in-field sales staff accessing remotely to web. Book-keeping is done remotely, but AR transactions need to be done locally, and feed into remote DB which holds all transaction information and also allows for reporting to book-keeping, sales staff, etc. I have current text-based applications zip I can provide to demonstrate current environment and needs, and additional requirements documents to explain the above, in more detail. Timeline to complete is by end of September to test and review application in detail, or sooner based on developer's hours.