The neighbour was not cooperative.  

But these markets are more of in an equilibrium so no big opportunity as it was US in 2012 and 2013.London is completely inflated in residential commercial is much cheaper.Other European countries could be a great opportunity particularly Greece and Portugal but they have not hit bottom yet, rental returns are low despite a 40-50% decline in prices and I don't see prospects for a fast recovery yet.  

@Nick Van Dyk For sure, I'm a big fan of knocking on the neighbour's door and hearing what they know.

What did cause pain was a fire in 2013 - - circumstances beyond control - - but even then the MFU saved the day and was net positive all the while.btw: my fixed expenses are 30% and no where near the inflated $5k example shown.When I bought, I determined the fixed breakeven point as 70% occupancy and never suffered anything near that.When the UK exits the EU, Greece & Turkey collapse, THEN we will see issues hard to deal with.

Confirm the dog is getting into your yard, Speak to the neighbour and advise them your tenants will be calling animal control if it happens again.

They cause damage , they stink and neighbours complain.

If I were your neighbour making a claim on my insurance would not be a option.

Typically when this happens, neighbouring property owners are advised and there is a window during the process during which you can file any opposing position.

His grandfather came to London from Greece with pennies in his pocket as a young man and grew these assets for his family, there is an attachment that goes beyond just finances. 

Your neighbour is going to keep a very close eye on you now and you are not going to get away with any tricks.You should cut your loses now rather than wasting time trying to do something that in the end is not going to fly.