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Using a self-directed IRA to buy vacation condo, rent it out to an LLC for $1
I don't quite understand your thought process here.  First, in a tax-advantaged retirement account you are NOT allowed to engage in a transaction with yourself.   If you just want to run a business and be able to write off expenses, how is using the self-directed IRA relevant? You can either buy the condo using your tax-advantaged account and rent it out to regular tenants.  Or you buy the condo yourself using your own money and then operate your business so you can deduct business expenses from doing so.  401k's allow you to take a loan out of it, so you can look into that as well.