Once you know what is legal (seeing other listings in a particular area does not count as people do it in illegal areas all the time). 

Here’s how you can stay informed and ensure your rental properties meet all legal requirements.1.

I just want o let the selling party my intent.

If you want them to leave, provide them legal notice to leave.

Most deals I work, I find that the most inexperienced party in a real estate transaction will end up losing 4-10% of the value of the home in the transaction because they don't know what they are doing. 

If you need financial help, ask under the "Finance, Tax, and Legal" forum.

Or a legal perspective?

It’s a win-win situation for both parties.4o

I am obviously conflicted with the moral side of pursuing legal action here, but understand that people can do untruthful things when it comes to financial gains. 

This is advantageous bc later you have a third party loan (not your personal money) so seasoning period is 90 days to DSCR out.