Wow, that’s an eclectic list! You don’t state where you’re thinking about pursuing these possibilities, but of course the larger cities offer more opportunities. I would guess that it would be difficult as a foreigner to do RN work, but that’s strictly a guess. For both real estate and tourism, yes, some gringo-oriented businesses might need some help. You’d need to have “boots on the ground” for awhile to establish credibility, and to do real estate properly would require a vehicle.