Quickbooks, Quickbooks Online, Peachtree or MAS90 Interface

Each interface is different:  Quickbooks is discussed in detail

Seamless integration into Quickbooks.  No exporting files and 
     importing into QB.
Retrieve setup data from Quickbooks and set CSS accordingly
Quickbooks does not have to be open when updating
Multiple locations can use individual QB data files OR CSS can
     update quickbooks using classes if using a single QB data file.
Quickbooks can be updated remotely via the internet for all remote
     locations.
Works with the higher end versions of QB.  Professional, Enterprise
Saves you time and money in the long run.
CSS can verify accounts with QB prior to posting!
Pre-Posting reports can be run showing what is being sent to QB
Simple Click and Send Operation