You need to study your state landlord tenant regulations and ask for a opinion from a legal rep familiar with the codes.

To my knowledge I am not  aware of codes that will legally allow renting a in-law suite.

I personally would rather lose a few bookings here and there, than put myself in any possible legal trouble. 

No legal advice given.    

That's the best way for a ton of legal reasons.

@Thomas S. so we can give advice and we won’t be in any legal issues? 

Or would their be legal repercussions if they do background checks and they find out that they don't want to rent to these people?

That means that he is legally required to work in the seller's best interest, which usually means getting the highest possible price, at the best possible terms and closing on the timeline most beneficial to the seller.As others have pointed out, getting a buyer's agent is at no cost to you. 

Are there any creative but legal ways to use my personal funds and the SDIRA on the same projects?

Some HOAs put restrictions on the number of rentals in a given community (such as 30% of the community can be rentals while the other 70% must be owner occupied), and once that limit is reached, the HOA won’t allow another rental.