The question is, what is the intention  of the owner, not what would a reasonable person think is the intention of the owner.

Depending on person it's in the teens.

A new person moves in and she says the upstairs neighbors are creating a ton of noise.

For example, at the start, do you confirm if all persons in the house are aware of your presence, and do you ask if it is OK for you to open bedroom, bathroom and closet doors?

Figure out which best fits you and your personality and take it from there.  

The person had something of an accent.

Personally, I find BTRs to be more predictable with fewer ongoing maintenance issues, and they tend to attract high-quality tenants.

He’s not a pushy salesman, and I’ve got a business partner who has worked with him for the last 10 years without any issues.As for your situation, I wouldn’t say it sounds like a Ponzi scheme, but I’d strongly recommend meeting with the fund sponsor in person and asking as many questions as you can.

I typically don't comment on other's businesses unless I know from personal experience.

My business partner owns a roofing company but has weak credit and more limited cash flow.An LLC is a common choice for partnerships since it protects personal assets and simplifies tax management.