Since I write the software and for small to large businesses, let me state an ipinion?
accounting is accounting and size is just how much is put in. One makes a chart of accounts to start a company off and the accountant can add to that base as needed. Reports for that are numerous and have to be able to access the added chart accounts and a thourough manner. Those reports are really for internal use.
CRM is, in some cases, where you keep track of clients and make your invoices as well as reports to show what they have done in the past. Totalling reports that can take in geographical locations(small or large) and produce reports are derived off the crm side. for simplicity, i am including sales into the crm.
CRM is generally software created by programmers with the specific nature of the company built in. accounting can be used for any business of any size.
it is wonderful to have the crm feed information into the accounting system at the close of a transaction. It makes the accountants job easier.
Wanna make money? Create some of this software(easy part) and sell it(hard part).