When you are free? Please do not award me, I need some discussion on the API limitation with you.
Please find the below some points:
> For an application to synchronize with QuickBooks, the application must be associated with a data realm in Data Services, which is associated with a company file in QuickBooks. Setup consists of steps in QuickBooks and in the IPP application, performed both by the user and the developer.
> In QuickBooks, the user sets up Sync Manager, according to these instructions. The company file information, including the company ID that identifies the data realm, is created for that user in Intuit App Center.
I need to use QBXML SDK to manage the requirement and need to synchronize the files accordingly.
One more thing for storing the files in Dropbox or drive:
QuickBooks loosely supports cloud storage such as DropBox and Google Drive. That's why it doesn't work well with these applications because QuickBooks files are always syncing, keeping working files in cloud storage can cause data integrity problems. So, don't keep the working file .qbw on Dropbox, Google Drive or any other cloud storage. This can corrupt your data file.
However, you can make a backup, create a portable file or an accountant copy of your file and save it to Dropbox. Instead use a Intuit authorized QuickBooks Hosting provider to have multiple user work on QuickBooks files at same time.
I will wait for you to discuss in details, let me ping when you can manage free time.