Minnesota just passed a law requiring all remote sellers to collect sales or use tax if selling in MN. But, they do have a small seller exception which does not require remote sellers to collect sales tax until their sales during a period of 12 consecutive months total either:
• 100 or more retail sales shipped to Minnesota
• 10 or more retail sales shipped to Minnesota that total more than $100,000
Also, for Amazon sellers, they collect and remit sales tax right now for WA, PA and one other state, but the seller has to collect for other states they currently have nexus in.
Some states are origin bases, some destination based.
Very complex and it's only going to get worse. Good opportunity for Intuit and Avalara to shine by coming up with an easier solution.