The property will be strictly for investment purposes, not a primary residence.I’ve been looking into two potential financing options:Hard Money Lenders (HML) – I’m drawn to this option for its speed in closing, but I know the rates can be higher.DSCR Loans – This seems like a great option for long-term rentals, but I’m unsure if it’s the right fit for my auction property since it might need some rehabbing.I’m also considering purchasing through a land trust or an LLC to add a layer of protection and privacy.So, my questions are:What’s the best way to approach financing for auction properties?

I also doubt very seriously that any brokerage/custodian is going to allow this kind of loan with 401k assets; it's likely going to need to be a 401k general purpose loan, which is highly regulated (as someone else mentioned). 

This protects against potential claims and liabilities specific to the rental.For tax purposes, maintain clear records of rental-related income and expenses, allowing deductions for insurance, utilities, maintenance, and depreciation proportionate to the rental unit.

The first main purpose of real estate investing(or any other investing) should be the return you are getting.

@Al JeciusAre you in City of Flagstaff or Coconino County for zoning purposes?

I sense a bit of "purpose" that is driving you that you may not have thought of.

You can choose to report your income and expenses on Schedule C by electing to file as a Qualified Joint Venture instead of filing a partnership return.If you have created an LLC that is not in a community property state, and as husband-wife you are the only members, then you are a partnership and must file a partnership tax return unless you have elected to treat your LLC as a corporation for tax purposes.If you have created an LLC in a community property state, and husband-wife are the only members, then you are a partnership and must file a partnership tax return unless you have elected to treat your LLC as a disregarded entity or corporation for tax purposes.

I'm trying to avoid having to use a PM for cashflow purposes yet the only LAIC I can find will only do it if the property has a PM. 

Those property use codes may come in handy for other purposes, such as when my municipality is aiming to ban STRs.  

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