Dear lostsoul65
ok- I know I likely don't know anything about what you're planning, thinking, or asked here on 07/04/16, "What should I do",
BUT, I feel I must comment NOW
on NOT where you should go,

BUT WHAT DO YOU MEAN BY ,
"couple of months of serenity before I die...
...and just fade off peacefully"...to go anywhere to check out..."
??????????

Your spirit matters, not your physical location.
--Please tell me I misunderstood your statements, and you're not really going through all this extensive planning,
only to find a pretty, peaceful, serene place to orchestrate the end of your life, aka suicide???

Note: I quickly looked at your profile, 7 posts in 9 months, no friends listed, and you've discussed things such as,
"depressed for 13 years"...Your Japanese wife called police and left you because she thought you were poisoning her food...Sold your house in March to move to a retirement center...You're in physical pain...Moved to Las Vegas WITH your ex-wife...

If I understood the key points of your post (above in red), need to remind you that death is permanent, and everything you're planning and thinking about is just wasting energy that would be better spent fixing the issues in your life, that are making you miserable and depressed.

Your biggest problem, like my own, likely is, as you said,
"all alone in this world"

I too and most comfortable in pretty, serene, quiet places, but I also know I've felt happy/content too at times in my life when I've lived or been stuck in awful places=
And why? Because of the healthy people/relationships and good health, I had in my life during those times.

Always, it's not where you are, but how you feel that REALLY MATTERS.

Please reconsider focusing your energy into WHO surrounds you, instead of WHAT surrounds you - And also improving your physical health.
I hope that will bring you (and I) the peace + joy + contentment we desperately need to enjoy life.

Trust me, I know how important a home is (I don't even have one right now), but if I read your comments accurately, where you physically are, simply will not fix the biggest problems, you're now faced with.
I hope good things come your way, very soon.