In order to do the will you should go to a spanish notario.
Notarios are the persons who make the will in public document in order not having unterior problems.
The best way is to translate it into spanish and go to the notario then.
The aplicable law it is your law, because you only are doing in spain the will.
The will is valid in Spain and in your country of course.
The price could be 90, 100 euros, once it is translated into spanish.
I am an spanish attorney, if you have a doub about how to do it just ask me
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