Welcome HVAC...some brief answers. These issues have been discussed many times here so you may want to dig into the specific threads for deeper discussion using the search function.
1. You will find it extremely difficult to work in other countries as they generally prefer not to employ outsiders on tourist visas to homegrown talent. You may be able to pick up a little here and there off the books.
2. Steel comes with its' own set of problems in salt water. Also buying a steel vessel and being assured of its' integrity is not easy. Most steel boats sail like pigs. If you are worried about collision (not at all likely) with hard stuff at sea...you can get glass boats with kevlar or similar bow reinforcement and watertight forward bulkheads. Thinking back, I can't recall one pleasure boat in the last several years that sank due to a collision with a container or other flotsam...though I am sure someone will dredge one up.
3. NO...expensive and a big draw on batteries. Not practical.
Worry about wind, waves, weather, boat construction and poor maintenance...the things that will REALLY sink you. Get a raft and an EPIRB and insure the boat.
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