Steps I took before retiring abroad (to Thailand):
1. severed all connections to my home state (NY) to avoid any tax domicile issue later: surrendered NYS driver's license, sold off all property, etc. according to the specific tax domicile rules of NYS. God help you if you are leaving Virginia.
2. Opened an account with a mail forwarding service, Mail Forwarding Services at St Brendan's Isle
(highly recommended). Service must be located in a no-income-tax state, eg. Florida, and should provide a street address, not a PO box. Updated address information with all banks, brokers, etc. while still in the US. I have never notified any institution of my current physical address, only the mailing address in Florida.
3. Opened several bank accounts since after having moved abroad it may be difficult or impossible to open a new account and the relative merits of each bank's services are likely to change over time. Bill pay features are relevant because I will always have some bills, e.g. credit cards, to pay in the US. The best banks are those that cater to a military clientele since they are not alarmed if they find out that you live abroad. Recommend USAA Federal Savings and Pentagon Federal Credit Union.
4. Bought an Ooma voip phone device and ported my home phone number to it. Not the cheapest solution, but high-quality product and service. After arriving in Thailand, plugged the Ooma device into my router and now have free incoming and outgoing US service with the same phone number I had for 30 years in New York City. I probably have the only 212 number in Bangkok. If you go the Ooma route don't buy their current Telo product which has monthly charges. Get the original hub on ebay or somewhere. That product has no monthly charges at all.
5. Selected a bank in Thailand that can accept low-cost ACH transfers from US banks. There is only one such bank in Thailand. Bangkok Bank can do this because it has a branch in NYC and therefore, an ABA number. Other countries may or may not have such a bank, but some banks will have lower charges than others for transfers.
6. Opened a variety of US credit card accounts, since I cannot be sure of being able to open one in the future. However, I subsequently did open one with Capital One without any difficulty. The key for the credit card is that it reimburses all ATM charges and does not charge a foreign exchange transaction fee. Penfed and CapOne cards meet the requirement. There are others that do as well. I make sure to have at least some charges on each credit card every month so that they are never closed for inactivity.
7. Switched reporting on all financial accounts to email only. However, there will still be snail mail occasionally, such as tax statements at this time of year. The mail forwarding service scans them for me to read the next day.
As an expat with US investments your big financial problem long-term is currency risk, which dwarfes inflation in importance. This is assuming that you keep your assets in the US, which is what most of us expats would recommend unless you were to move to Canada, for instance. Start reading books by economist Barry Eichengreen.
You need to make sure that you have a health care solution in your new country. I plan to sign up for Medicare at age 65 even though I can't use the services while outside the country for two reasons: I can never be sure that I will stay forever in Thailand and, even if I were sure of that, I will always need US insurance during annual trips to see the family.
As for destination countries, I wouldn't consider Ireland myself because the cost of living is high. However, I can see the attraction since Ireland was recently rated by somebody as having the best quality of life in the world. Asia has the advantage of lower cost of living, at least in most locations, and relatively lower levels of crime. Latin America would be attractive to me, but for the crime problem, although I am sure there are effective ways of coping in many areas. I have friends who love retired life in Mexico, but the potential for crime there to expand into currently safe areas would certainly give me pause.
I never plan to own anything in Thailand. Renting an apartment is the overwhelmingly best choice here for many reasons. I hire a car and driver when I need to get out of Bangkok.
My other advice is to study the local language full-time until you are fluent. As an older person the mental benefit of language study in itself is substantial. And then, in terms of the new culture you can be a competent person.