You are a local investor with a couple properties, not a conglomerate, and you are looking to get one more and the open market is dry.

Whenever I see a new guru or some "new method" especially, when it comes to mortgages, I always ask, what is this person gaining?

I have been watching the markets for the past year or so looking for a property that I can use the BRRRR method on, but what I have been seeing is that the homes that require work are selling for WAY more than they should in their condition.

Contact insurance immediately and get that place dried out, fixed up and re-rented asap. 

TL;DR. I

Then determine your method.    

I understand vibration cannot be dampened, but I think voices and music would be dampened by this method. 

When you start to feel like you are starving for real estate, you are fodder for everyone out there who wants to wholesale you a dump on seller finance or some other quick method that won't work.Your only job if you want more real estate is to create more capital for yourself and more equity in your current home.

That's why I do "constructive evictions" which includes a variety of methods like asking, telling, threatening, starting the eviction but stopping it when the tenant leaves, etc.

I'd like to apply to BRRRR method in Portugal but I'm struggling to understand how to do the refinance part.