That violates the Takings Clause.MD can be distinguished (in fact MD was mentioned in the decision) in that there IS a process on the books for the foreclosed owner to petition the court for the surplus. 

When it comes to getting approved for a loan, the process can be a bit more complicated for foreign citizens.

And before getting too far along in the process it might be worth doing a title search to check on any potential liens on the property.

If you are not looking to evict now, I'd wait with these types of tenants until closer to the 30 days, you are looking for more confrontations and problems if you tell them you won't renew. if anything,  you can say that if there will be another violation you will start eviction process best of luck 

I’m temped to order an appraisal this month, or does that seem like over kill and do you recommend I sit back and trust the real estate process?

Then you put another portion of your mortgage on the HELOC and repeat the process. 

@Michael Smythe Great processes Michael!

I need to do some research on what credit score I need to actually begin this process 

Are they going to put you through hell during the process, and are you okay with it?

@Alex Washburn makes really good points - the process is definitely not easy.