I'm sure the same visa requirements would apply here, but would be more difficult to prove...I suppose. More chances to accept under-the-table monies for sure. I had actually thought to be a Madrid tour guide some day (I even own a domain name that will help in this endeavor if I decide to JUMP IN).
I have an e-friend, Steven Drake-Jones, who gives historical Madrid tours on behalf of Welltours (find his URL on my LINKS page @
http://www.MadridMan.com/links.html ) and he mentioned to me long ago (if my memory serves) that you have to get a kind of street permit from the city before you can take part in this kind of business, sort like what street vendors and entertainers have to get in order to conduct business outside of an establishment.
Good luck!! Saludos, MadridMan
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