@Cameron PriceI agree with comments above that if you qualify for the Solo 401k plan I don't see any reason why SD IRA would be more beneficial (unless you have funds in a Roth IRA like Chris).

I am willing to sacrifice convenience – and also some money – if it has a big impact on my ability to qualify for a mortgage in 18 months.  

First of all, most flips don't qualify for cap gains.  

I know most of you would tell me I should be pre qualifying leads before actually wasting my time to go to the property, but I wanted the experience of walking through houses, learning to build rapport and improve my sales skills.

As of right now, we do not qualify for financing these large deals so it is a way for us to build assets/credit history. 

And I'm nervous about refi-ing the condo, renting it out, and buying a multi-unit bc I'm not sure if I would qualify for a mortgage for the multi-unit because our student loan balance raises our DTI. 

The holder of the debt.Do not charge fees, it's not a finance company.Interest is as agreed, you need to check usury laws for the state and stay under that rate, generally usury law will not apply in a commercial loan.A note is not a qualifying asset for an LLC as a capital contribution for compliance where capital may be required.Look up sham transactions as well, I have no idea what you're trying to accomplish.

The only danger is the banks due on sale clause so make sure you can qualify to fiance a new mortgage @Brian Gibbons is an expert on subject 2 transactions and he can further help you Good luck

I won't say they don't exist, because I know several that are appropriately licensed and can make these loans, but they tend to specialize in lending to well-qualified borrowers that the banks won't touch.

In 2008 I sold my commercial property formally known as Buffalo Radiator (63est Utica..