I have clients using QuickBooks for Mac. I like to work from my office and they like to keep QuickBooks on their machine. Of course, I can take control of their machine with any number of applications and do my work directly on their machine.
An easier, free method is to simply share the data file using a Dropbox. With this method, each computer will have its own copy of QuickBooks for Mac and will simply open the data file stored in the Dropbox.
A caveat: The QuickBooks file can only be used by one person at a time. If it’s open and in use by more than one person, you’ll end up with “conflicted file” copies. I solve this by letting my clients know which days/hours I’ll be updating their books.