This is certainly a good function to consider. The key I believe is to find the correct table / spreadsheet layout for Manager, put the data in and import using the buttons provided. Once the format is determined the spreadsheet could be potentially populated with data from any other piece of accounting software. I have just done a quick test with Manager inventory. If you export the Inventory to file then check OK in a spreadsheet and confirm data correct. Next I followed the import instructions and I found the inventory Description imports OK but without the Item code and Item name, also the pricing is missing as well as the Qty on hand.
I read somewhere we need to add a column StartingBalanceQty is TRUE but it has not resolved the incomplete data population problem.
It would be fantastic to have knowledge of what the headers ought to be in the spreadsheet layout so that this can be achieved seamlessly.
A closer look reveals that Manager allows you to download a template
Continuing the discussion from Using batch operations on inventory items:
It works.