I realise that you have California and Florida that matches Spain's climate, but the culture naturally is different here, and that's what makes it interesting.US citizens can of course invest here the same as any European.

Use the magnifying glass on local FB groups and search for "housekeeper" and also use the enemy method. 

Does anyone have experience with this method, within this region?  

Use the enemy method! 

Seeing with eyes and staying there a  few days would help, also check out using enemy method and also Facebook groups

My husband and I are in the same boat with a VA loan, and being told that since we itemized and deducted so many repairs, etc last year from our new rental that we can not count any of the 3k in rent towards our income, and so the 2850 mortgage payment doesn’t offset and therefore ruins our chances of getting a mortgage :(  If you can show the repairs are one time in nature, not just typically maintenance , you can add those losses back.

And we can nitpick 1%, 2%, & 3% based on our own methods of calculation and what we are individually seeing.

Hello everyone,I've been closely examining a property listed on Redfin and am curious about the estimated rehab costs for a project of this nature.

I still feel the best method is asking other real estate investors in your market (which he does mention in the article). 

There are problems and risks involved that is the nature of it.