My name is Lucy and I'd be happy to answer your questions today.
1. You will need to register as an LLC in any state where you do business
or maintain a substantial presence. So, for example, if you were a CA company, but you stored all your goods in warehouses in Nevada, you'd have to be registered in Nevada. If you were employing outside sales people to sell things in Oregon, you'd have to register in Oregon. Maintaining a website that happens to sell a few items in a state is not the same as doing business there. However, if you start advertising in a state and targeting business at that state, you would likely be found to do business in that state as well.
2. The Secretary of State can often be used as a registered agent for service of process. Some states require that the registered agent be in state, so you could not be the registered agent states you don't live or work in.
3. There are advantages to becoming an LLC, including reduced taxes and limited liability (for example, you would not be personally liable for corporate debts and vice versa). Those are the primary reasons that people incorporate. Another benefit is that, if a person tries to sue you in another state for products you sent, jurisdiction
would be based on whether the business has contacts with the state, and not whether you personally have traveled to the state or maintain contacts with people that live there. Also, an LLC cannot sue or be sued without hiring an attorney to appear in court (whereas you could). Those are some things to think about, on top of the cost of incorporating and registering as an out-of-state corporation
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