@Ricardo DiazYou are filing your taxes incorrectly if the property is owned as tenants in common and you are reporting 100% of the rental activity.

We’re familiar with the more commonly discussed routes of how to go about doing this, such as:Going to friends and familyCrowdfundingEquity/HELOC/House hackingPrivate moneySubject to/wholesalingPersonal loanRetirement borrowingGrantsBut we’re pretty sure we haven’t thought of everything. 

To your point, 75% leverage doesn’t always work—65% is common.  

The obvious ones are saving them the hassle of listing, and saving them money on agent commission if they choose not to get an agent; but I am sure there are other creative suggestions out there.Is it pretty common for the buyers agent to act as a dual agent in situations like this?

@Kenneth Rolfe same as @Mason Hickman, I've done this a few times, but it's not common.

Unfortunately that is a very common thing here.

Allocating common expenses - you can allocate common expenses based upon a formula of # of bedrooms used or square footage of each unit.

Disclaimer ahead of time: not a lawyer, this is not to be taken as legal advice.That said: this all boils down to common law.If I want to sell you my shirt no one can tell me I need a license to do so.

Some states have certain legal requirements but for the most part, 30 days notice is common.

The most common and effective way to do this is by calling buyer, FSBO, and expired leads.