Reassure them that you will be complying with the laws...no late night parties & no criminal activites!

Or How do I comply without spending THOUSANDS?

This protects all parties on the agreement should one party not comply. 

There may also be zoning and/or if applicable HOA rules to comply with.   

Since they are month to month, you can likely give them 30 days notice on non-renewal (pending confirmation that is what the current lease states and that notice complies with your local laws). 

So worst case scenario is now you have to comply with NV laws AND your local laws - it's rarely worth it. 

., will the new unit have to comply with the residential building code?

You can sometimes get away with not complying if the occupancy is lower than a certain threshold. 4.

@Mark GreenawaltFor what it's worth, 99% of the wholesaling contracts I run into are nowhere close complying with Pennsylvania Law. 

But now the Industry Guidance requires all persons entering the property to 1) comply with the Posted Rules of Entry as a condition of entry, and 2) agree to the prevention plan.