Hi there Kalvik,
It's important that all your transactions are correctly entered for your books to be well balanced. QuickBooks Desktop is a great tool able to help you keep track of sales and expenses so you can see the profit of your company. I can provide some information about Items.
The limit of items includes both inventory and non-inventory items. To see the full list of list limits in QuickBooks Desktop, you can consult it here.
If you have any other questions feel free to reach out here.
