When purchasing a property with your Solo 401k, the 401k trust name should be on the purchase agreement (closing documents). You may also be listed as trustee on the purchase agreement.
The process for selling an investment property is done in reverse. When selling the property, the seller should be listed as the 401k Trust (maybe with you also listed as trustee), and any check/wire/payment needs to be sent to the plan trust bank account.
Never have funds wired or sent to you personally for an asset that is owned by the Solo 401k trust. Never have funds wired or sent to your business for an asset that is owned by the Solo 401k trust. Keep things clean and have all funds from the sale of an asset sent directly to the 401k trust bank account.
For example, if your 401k trust is named Johnson Software Trust, and your 401k is selling real estate, the sell agreement should list Johnson Software Trust as seller. Your bank accounts and/or brokerage accounts should be in the name of Johnson Software Trust.
When supplying a Tax ID number for any 401k transactions (including the opening of a bank account), always supply the EIN (Employer Identification Number) assigned to your 401k trust – NOT the EIN for your business. This trust EIN can be found in your 401k plan documents on your Solo 401k dashboard.