1-2 years vs retire are vastly different numbers.
IMO one of the biggest $ drains when traveling is the actual moving around. All the extra money spent on plane tickets, board bag fees, taxis to/from airport, etc adds up quick. To save money you are better off posting up for 1-2 month stretches. Find some kind of rental where you can cook your own food, unless you are in SE Asia or somewhere cheap where the savings are negligible.
I could probably keep it to $2k/month for a year. Some destinations I could probably half that relatively comfortably. Although it’s been a while since I’ve done a trip like that, so what I paid at the time could be vastly different now.
If I were retired, I’d want enough in high yielding money market or conservatively vested fund where I could draw $2-3k month in interest without touching the principal.
As for health insurance, that’s relatively easy. There are tons of travel insurance policies, and lots that are geared towards expats, that are very affordable compared to what we have here.