Editions of Salesforce

Details	Group	Professional	Enterprise
Indicative Pricing (see Pricing)	AU$35/user/month	AU$95/user/month	AU$180/user/month
Think of it as	A Contact Management app with a great mobile app Lead management	A shared excel spreadsheet in the cloud, with basic tracking of sales	A full enterprise level platform for all business areas except accounting, warehousing / distribution, specific verticals
Integrations available	Web to Lead only	API available at a cost	Almost anything you can imagine
Apps available	very limited	Limited even some apps that use the API may not be available if the API is paid for	(but many at a high cost - see Appexchange Apps).

Note, based on Sales Cloud - see also Service Cloud and Marketing Cloud for other options

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