If you want to write an invoice to QuickBooks, you must duplicate all database entries that occur when an invoice is created in QuickBooks--or risk serious data corruption in QuickBooks. The tricky part would be trying to figure out what all of the database entries are. I would recommend a QuickBooks developer for that.
I havent used this product but I have heard from others that have and like it.
On a side note, if you need a reference with someone who has experience with FM / Quickbooks integration please contact me back channel and I can give you a reference.
I've used the FM Books Connector plug-in extensively to integrate our accounting data with QuickBooks. It works pretty well, all things considered, but there are definitely drawbacks. Here are a few things to know:
1. FM Books Connector only works on Windows machines with Windows QuickBooks and it does not work in a served environment; it has to be done on a client machine with somebody running the show, i.e. somebody has to push a button to launch whatever data integration is necessary.
2. Syncing will not be possible because pulling data out of QuickBooks into FileMaker isn't possible.
3. Our biggest hurdle is translating our data structure into QuickBooks' data structure so it can be pushed to QuickBooks, and QuickBooks' data structure is less than ideal, to put it mildly.
4. Integrating with QuickBooks is not going to be easy by any means; it will be hours upon hours of development and headaches. We spent a good 50 hours integrating QuickBooks with our FileMaker solution.
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