SEP IRA SOLO 401(k) or Roth Solo 401(k) to direct your funds

[Account Closed]

I hear a lot of talk about Solo 401 (k) being the best vehicle to set up for a retirement plan and then set up a self directed IRA to fund a portion or all to invest in what you choose. My question is this: how do you know which is the best for you to choose from as there is SEP IRA , Solo 401k & Roth Solo 401k.