Create a TMS based on my Excel "programs"

TMS = Transport Management System. While this system would be used primarily for myself, if possible I would like to offer it up for use by others, likely SAAS / monthly membership fee. I am a freight broker and currently using Excel with macros etc that I've built & modified myself over the years. I am looking to have a software system built that would be faster for sorting, searching, updating etc. I want to add in more automated tasks (ie click a button to send an email for a specified task, automatically send statements for past due invoices on the 15th as example), EDI capabilities for automatic tracking shipments through supplier websites. I have looked at many companies out there offering this type of software, however nothing really matches how I work and some that come close are either much too expensive for a small business like mine or very bloated in additional features and "extras" that are really not required. Seems like everyone nowadays is just adding as many bells and whistles as possible as selling points. This is not what I want to do. For this program I would say there are multiple databases within the 1 main system: Quotes, Rates, Orders, Customers, Vendors, shippers & receivers + the accounting side of things with invoicing / receivables, payables etc. All would have to be able to interact with each other to avoid duplicate entries. Ideally looking for something that would be multi user. I have a few ideas depending what may be possible/feasible. My main idea would be having more than 1 user working on the same order form at the same time. I believe this would be best suited as a website / online service as in future I would like to add capabilities for clients to log in and be able to retrieve certain information (like order tracking and pricing requests) and download documents. With that in mind, I am not opposed to a stand alone program. Whatever would work better, be it a stand alone that would in future be able to update a website automatically or be 100% online with secure login. In future I would like to have the possibility of a customer portal (for the above mentioned reasons), maybe a phone app to be able to work on the road. A few key items I am looking for: Keyboard friendly - meaning more keyboard navigation with tab/enter instead of clicking all over across multiple pages. This business has alot of number entering, so moving your right hand from the mouse to the num pad and back to click and back to num pad is something I want to avoid, ie, using the tab/enter keys. There would need to be an easy backup/restore method installed. Obvious one but should not assume right? Autocomplete when typing in a field, but able to hit the down arrow and enter on the highlighted selection to choose it (no mouse clicking required). Available to export to excel or csv. We all love seeing our data in Excel. Timestamp tracking of all changes. *While not necessary, possibility of integrating with QuickBooks or other accounting software.