What you should be most concerned about retirin
What you should be most concerned about retiring abroad is to obtain a permanent residency in the country.
You should consider the residency visa options and requirements of the country and determine if you would qualify for one of them.
Panama, as most countries, has different programs, so your visa program choice will depend on your intentions (recreational, investment, retirement, etc.).
Also one of the most important considerations when you retire abroad is to find experienced professionals who have good references. This advice applies to everything from an attorney to a gardener. This will save you from inconveniences and will let you feel more relaxed in your relocation.