Copywriter system, plugin or CRM

I want to build a system where copywriters can do the following things.

Any wordpress plugin, any cheap or free CRM system you can reffer

• They can login via username and password
• Upload a word document or image
• Count the words in the document
• Some extra text filed [ i.e write excerpt, tag and title of the page]
• Calculate the payment according to the words in the document [250 * £1]
• Provide summary, how many articles copywriter in a month and payment due

Any help would be much appreciated.