A lot of 'off-grid' places are not, which will lower their value and resale ability.Also, you are decreasing your potential market by choosing a venture like this..not everyone will find composting toilets as cool as you and I might.Having said that, I think it could be a great find, if it check all the the boxes.

They'll have the same issue with the next buyer and you can always come back in a few months and make them a much lower offer once the property has fallen out of contract a few times and they are extra motivated to sell.   

I would definitely factor in some substantial capex/ maintenance and repair costs which could lower your returns.  

Some of these areas have lower purchase prices but solid rental demand, making them ideal for strategies like BRRRR.I spend my time scouting off-market distressed properties, and I’ve noticed that investors are having a lot of success in secondary cities just outside major metro areas.

Ideally, no more than 5% over median and no lower than 15% under median.

Or if you want to swap higher returns for lower maintenance you can look in to FIG (fourplex investment group_.

@Carlos Ptriawan how do you mean, "management required the LTV to be lower than 50-60 percent" ?

So, yes, you'll get a lower percentage of the cash flow (which isn't that high anyway for long-term rentals like pretty much anywhere in the world, including the US) but you'll get appreciation and loan amortization.b) You successfully invest in STRs and make enough money that you don't care that much about the higher taxes.To conclusion, as a foreigner investing in Spain, with a few exceptions of specialized niches, I focus on areas that have (high) capital appreciation and short-term rental potential.Hope this helps.

Also see if monthly gap might be lower as a mid- or short-term rental.

Congrats on your success in acquiring the duplex that now will yield 6.5% cap at current lower rental rates. 94115 is a great zip code to be in.