The landlord has no interest in the personal property coverage, but they absolutely have an interest in the liability side.When the landlord is listed on the policy as "additional insured" it extends some coverage from the tenant's policy to the landlord in case of certain liabilities arising from the tenant's use of the property, like accidents or damages caused by the tenant's negligence.

Is there another option that I am not thinking of or one of the options listed above that you think would be best?

They have bots that look for every piece of furniture on the internet, create a listing for it, and then have it shipped if you buy it (often at a 2-3X markup). 

A squatter can see it's listed for rent with a sign or without so I don't think that'd be a huge concern.

I also like to check reviews on platforms like Yelp, Google, or even Angi (formerly Angie’s List).

I noticed their business is listed as an LLC on their Zillow profile, and we also found that they have a few other unrelated LLC businesses that didn’t seem to work out for them over the years and were short-lived.

Most reputable HMLs will not charge anything until you are sitting at the closing table and all fees will be listed on the HUD-1 closing document.And of course, what are the points, interest, and attorney/document/admin fees for the loan?

They list only either the opening bid for the property they are auctioning off ($50,000) or they don't list a number at all3.

You can simply list it as a $300k sale and list Seller Finance as one of the financing options in the MLS.

Would love to see some of those listings.