You don't need a CRE broker but you definitely want an attorney that specializes in CRE sales contracts or leasing law.....should you decide to go that route. 

I believe its the sellers expectations not the amount of money that's the issue.

I then check to see if there are any local laws that limit the number of STR rentals in the municipality.

I definitely never thought this would be an issue when I purchased my house.

I would want to have the deciding vote on any issues that arise.

Or if she has an ITIN get that but if you run an ssn or itin it only picks up US issues, not international. 

Like others have mentioned turnkey is a great option, there are several providers that operate east and north of you where the price points/rents are more favorable while laws remain landlord friendly.

I know some people who have tenants living above with no issues.

Or should it be on just getting someone in there and dealing with those issues in the future when I go to rent out the main living side?

Chris Prefontaine has broken many laws and I’ll be filing complaints this week with the Department of Real Estate in each state he is running these scams and handing over all the evidence.