ANSWER: Because the Fidelity account for the solo 401k is set up as a brokerage account, it will allow you to also invest in equities in addition to having a checkbook attached to the brokerage account for placing alternative investments such as real estate, and you can also process the solo 401k participant loan by wire.
Whereas the Wells Fargo account is a bank account for the solo 401k not a brokerage account you will only be able to place alternative investments not equities, but can process the solo 401k participant loan. If you decide to go with Wells Fargo let us know as we have a contact person and special paperwork applies. Same goes with the Fidelity account; if you want to use Fidelity let us know and we will prepare the applicable Fidelity forms.
Additional Resources
Solo 401k Investments
FAQs Solo 401k