Hello and welcome. Thanks for providing an opportunity to assist you again.
In that case, I would suggest going for SEP IRA and then put the surplus in Roth, which would be after tax dollars.
The following is a guide for your general information which tell you how to set up such IRA.
To get started, you will have to reach out to firms like Vanguard who usually takes care of all of your requirements, MORE SO IN UNBIASED MANNER and to YOUR BENEFIT.
Please refer : https://investor.vanguard.com/what-we-offer/small-business/sep-ira
I am sure this would help.
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