Should I get the police report and send a letter to the upstairs tenant reconfirming with them the stipulation in our lease of quiet enjoyment? 

If you are this close to the border or cost you need to purchase through a corporation or through a bank trust (Fideicomiso - Think of this trust to be similar to an inheritance trust or a living family trust in the US.)At all times you are the legal owner of the property, the best way to see it is as a permit or license that allows you to purchase, use, enjoy, rent, renovate, inherit, etc. a property in this zone.

I really enjoy the property manager, they're getting 4.9 reviews for it and their team is great to work with.But I’ve only had a handful of profitable months, most of the time I’ve been paying either the mortgage myself or unexpected cleaning & maintenance bills, and my savings has run to zero, so it’s a big loss so far.

I would imagine wherever she went the new landlord is enjoying her company.

I also enjoy the poster's contradictory claims, waffling and changing the rules depending on which side of the fence they are on.

They discovered that we feel a loss twice as hard as we enjoy a gain.

The main thing is to enjoy what you are doing in life  !!

Perhaps, this is the "big boys" room (big girls too) and it is your firm belief that your statements push people to greatness. 

A nuisance is something which interferes with someone else's comfortable enjoyment of their life or property.

per @Matt James comments.....I really do enjoy the creativity of the small space design concepts that go into tiny homes.