Moderator: I have no idea whether I'm in the right area or not. It was a best effort to pick the right discussion area. If I have errored, please move this topic as needed. Thank You in advance.

We are finishing a business plan for a local pkg/parcel/dock delivery service in a large urban market.
I am wasting many hours trying to find a app we can use to:
dispatch
map
integrate with GPS
track invoices
do Accts Receivable
track customer service notes and sales rep assignment and activity.

Can anyone point me in the direction needed. Does not have to be the King of the Hill vendor. If the app is dependable, supportable, runs on either Win or Mac, and the word SERVICE is appreciated, we are all ears.
Thanks in advance!