What are the major advantages of investment properties in Lisbon and separates it apart from other European cities/investments?

I could be biased, but I think Montreal would always be an attractive destination especially for Europeans and Americans (less so for Asians), and recently I heard Halifax and the maritimes are booming too. 

Within the European Union, the average home price in Lisbon is now higher than that of my hometown of Brussels, even though the average income in Brussels is so much higher and Brussels is the capital of the EU.

After Mark Cuban hired him finally, Luka Doncic hated him, so now he is out and owns part of a European soccer team where he does the analytics.TLDR: Your gambles should go along with the math of your life and your family. 

In any case, they were being eyed by a European giant - Aviva. 

Example Home Mortgage interest deduction disappears: I will sell my house to my brother who I will rent from- just like they are doing European countries.

may be- The TARP 2.0 is actually already happening @James Hamling, this happen in very private transaction for US to save "Credit Suisses" crises where US gov. is loaning cheaper dollar than normal to their European counterpart to save their banks.

It's also part of the European Union, which is a huge advantage.On the other hand, sadly, it's a total disaster politically, economically and demographically.

International money from China, Asia in general, some European, and there is still the lure of the beach!

they were built by first generation European craftsmen.