Thanks for joining the Community, @jason dao .

I want to ensure that you receive the best integration guidance from members of this space. If you could please post which version of QuickBooks that you're using, this will help to guarantee that you receive the best suggestions. 

A good friend of mine operates an e-commerce business and has often shared his stories with me. The extremes have ranged from not having enough products to meet the demand to then having so much inventory that he was having to hide T-shirts from his wife. Luckily, he has learned and keeps a healthy amount of inventory now. Should you ever have any stories or challenges, please feel free to share them. 

For tips and tricks to get the most out of your time in the Community, I recommend the following resources:

• Getting Started in QB Community!
• QuickBooks Community Guidelines

Looking forward to hearing from you! 

Thanks a lot for your recommendations. FYI I used Connex for QuickBooks app to integrate Quickbooks and Shopify. Let me tell you the app worked so well and I've done the task in just a few simple steps. I found the app after reading this article: https://avada.io/shopify/integration

Connex is a good connector for Shopify and QuickBooks (i.e QBO and QBD). If you seek another option with lower cost, consider this app.

https://automate.io?ref=quickbooks

Hope it helps.

My company has built alot of these as custom applications.   Feel free to connect if I can help.  Also, APIWORX.com is a good solution for more complex integrations to marketplaces.