You are not allowed to solicit for money (aka ask or advertise) to strangers without following the guidelines.   

You are putting your property under a lot more risk than the average landlord, not doing background checks, and have a constant flow of strangers in and out, while not paying them any more in premium for the trouble.

As @David Faulkner stated, you don't need to show strangers your bank account, but why not to ask a best broker close to home to help you find some opportunities for your relative who has about a mil to invest?

@Herman Wu, while I agree with you that real estate has become almost a non-option here in the NYC metro area and I invest outside of the city myself, it can be risky to invest somewhere you don't know well and trust strangers to safeguard your best interests.

You set the policy, not some stranger.

I had a similar experience, except a property owned by a stranger, not from a friend.

I was just playing devils advocate, putting my skeptical self in the shoes of the owners receiving a letter from a stranger.

Take it slow until feel more comfortable explaining your goals and your current status to a stranger.

I can't imagine you getting 6 strangers to rent a bedroom and share the two bathrooms between each other... this sounds like a college dorm.

When entering the world of trying to raise money from anyone (strangers & family alike), you MAY tread into securities law.